cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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A060854 Array T(m,n) read by antidiagonals: T(m,n) (m >= 1, n >= 1) = number of ways to arrange the numbers 1,2,...,m*n in an m X n matrix so that each row and each column is increasing.

Original entry on oeis.org

1, 1, 1, 1, 2, 1, 1, 5, 5, 1, 1, 14, 42, 14, 1, 1, 42, 462, 462, 42, 1, 1, 132, 6006, 24024, 6006, 132, 1, 1, 429, 87516, 1662804, 1662804, 87516, 429, 1, 1, 1430, 1385670, 140229804, 701149020, 140229804, 1385670, 1430, 1, 1, 4862, 23371634, 13672405890, 396499770810, 396499770810, 13672405890, 23371634, 4862, 1
Offset: 1

Views

Author

R. H. Hardin, May 03 2001

Keywords

Comments

Multidimensional Catalan numbers; a special case of the "hook-number formula".
Number of paths from (0,0,...,0) to (n,n,...,n) in m dimensions, all coordinates increasing: if (x_1,x_2,...,x_m) is on the path, then x_1 <= x_2 <= ... <= x_m. Number of ways to label an n by m array with all the values 1..n*m such that each row and column is strictly increasing. Number of rectangular Young Tableaux. Number of linear extensions of the n X m lattice (the divisor lattice of a number having exactly two prime divisors). - Mitch Harris, Dec 27 2005
Given m*n lines in a {(m + 1)(n - 1)}-dimensional space, T(m, n) is the number of {n*(m-1)-1}-dimensional spaces cutting these lines in points (see Fontanari and Castelnuovo). - Stefano Spezia, Jun 19 2022

Examples

			Array begins:
  1,   1,     1,         1,            1,                1, ...
  1,   2,     5,        14,           42,              132, ...
  1,   5,    42,       462,         6006,            87516, ...
  1,  14,   462,     24024,      1662804,        140229804, ...
  1,  42,  6006,   1662804,    701149020,     396499770810, ...
  1, 132, 87516, 140229804, 396499770810, 1671643033734960, ...
		

References

  • Guido Castelnuovo, Numero degli spazi che segano più rette in uno spazio ad n dimensioni, Rendiconti della R. Accademia dei Lincei, s. IV, vol. V, 4 agosto 1889. In Guido Castelnuovo, Memorie scelte, Zanichelli, Bologna 1937, pp. 55-64 (in Italian).
  • R. P. Stanley, Enumerative Combinatorics, Cambridge, Vol. 2, 1999; see Example 7.23.19(b).

Crossrefs

Rows give A000108 (Catalan numbers), A005789, A005790, A005791, A321975, A321976, A321977, A321978.
Diagonals give A039622, A060855, A060856.
Cf. A227578. - Alois P. Heinz, Jul 18 2013
Cf. A321716.

Programs

  • Maple
    T:= (m, n)-> (m*n)! * mul(i!/(m+i)!, i=0..n-1):
    seq(seq(T(n, 1+d-n), n=1..d), d=1..10);
  • Mathematica
    maxm = 10; t[m_, n_] := Product[k!, {k, 0, n - 1}]*(m*n)! / Product[k!, {k, m, m + n - 1}]; Flatten[ Table[t[m + 1 - n, n], {m, 1, maxm}, {n, 1, m}]] (* Jean-François Alcover, Sep 21 2011 *)
    Table[ BarnesG[n+1]*(n*(m-n+1))!*BarnesG[m-n+2] / BarnesG[m+2], {m, 1, 10}, {n, 1, m}] // Flatten (* Jean-François Alcover, Jan 30 2016 *)
  • PARI
    {A(i, j) = if( i<0 || j<0, 0, (i*j)! / prod(k=1, i+j-1, k^vecmin([k, i, j, i+j-k])))}; /* Michael Somos, Jan 28 2004 */

Formula

T(m, n) = 0!*1!*..*(n-1)! *(m*n)! / ( m!*(m+1)!*..*(m+n-1)! ).
T(m, n) = A000142(m*n)*A000178(m-1)*A000178(n-1)/A000178(m+n-1) = A000142(A004247(m, n)) * A007318(m+n, n)/A009963(m+n, n). - Henry Bottomley, May 22 2002

Extensions

More terms from Frank Ellermann, May 21 2001

A262809 Number A(n,k) of lattice paths from {n}^k to {0}^k using steps that decrement one or more components by one; square array A(n,k), n>=0, k>=0, read by antidiagonals.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 13, 13, 1, 1, 1, 75, 409, 63, 1, 1, 1, 541, 23917, 16081, 321, 1, 1, 1, 4683, 2244361, 10681263, 699121, 1683, 1, 1, 1, 47293, 308682013, 14638956721, 5552351121, 32193253, 8989, 1, 1, 1, 545835, 58514835289, 35941784497263, 117029959485121, 3147728203035, 1538743249, 48639, 1, 1
Offset: 0

Views

Author

Alois P. Heinz, Oct 02 2015

Keywords

Comments

Also, A(n,k) is the number of alignments for k sequences of length n each (Slowinski 1998).
Row r > 0 is asymptotic to sqrt(r*Pi) * (r^(r-1)/(r-1)!)^n * n^(r*n+1/2) / (2^(r/2) * exp(r*n) * (log(2))^(r*n+1)), or equivalently to sqrt(r) * (r^(r-1)/(r-1)!)^n * (n!)^r / (2^r * (Pi*n)^((r-1)/2) * (log(2))^(r*n+1)). - Vaclav Kotesovec, Mar 23 2016
From Vaclav Kotesovec, Mar 23 2016: (Start)
Column k > 0 is asymptotic to sqrt(c(k)) * d(k)^n / (Pi*n)^((k-1)/2), where c(k) and d(k) are roots of polynomial equations of degree k, independent on n.
---------------------------------------------------
k d(k)
---------------------------------------------------
2 5.8284271247461900976033774484193...
3 56.9476283720414911685286267804411...
4 780.2794068067951456595241495989622...
5 13755.2719024115081712083954421541320...
6 296476.9162644200814909862281498491264...
7 7553550.6198338218721069097516499501996...
8 222082591.6017202421029000117685530884167...
9 7400694480.0494436216324852038000444393262...
10 275651917450.6709238286995776605620357737005...
---------------------------------------------------
d(k) is a root of polynomial:
---------------------------------------------------
k=2, 1 - 6*d + d^2
k=3, -1 + 3*d - 57*d^2 + d^3
k=4, 1 - 12*d - 218*d^2 - 780*d^3 + d^4
k=5, -1 + 5*d - 1260*d^2 - 3740*d^3 - 13755*d^4 + d^5
k=6, 1 - 18*d - 5397*d^2 - 123696*d^3 + 321303*d^4 - 296478*d^5 + d^6
k=7, -1 + 7*d - 24031*d^2 - 374521*d^3 - 24850385*d^4 + 17978709*d^5 - 7553553*d^6 + d^7
k=8, 1 - 24*d - 102692*d^2 - 9298344*d^3 + 536208070*d^4 - 7106080680*d^5 - 1688209700*d^6 - 222082584*d^7 + d^8
(End)
d(k) = (2^(1/k) - 1)^(-k). - David Bevan, Apr 07 2022
d(k) is asymptotic to (k/log(2))^k/sqrt(2). - David Bevan, Apr 07 2022
A(n,k) is the number of binary matrices with k columns and any number of nonzero rows with n ones in every column. - Andrew Howroyd, Jan 23 2020

Examples

			A(2,2) = 13: [(2,2),(1,2),(0,2),(0,1),(0,0)], [(2,2),(1,2),(0,1),(0,0)], [(2,2),(1,2),(1,1),(0,1),(0,0)], [(2,2),(1,2),(1,1),(0,0)], [(2,2),(1,2),(1,1),(1,0),(0,0)], [(2,2),(2,1),(1,1),(0,1),(0,0)], [(2,2),(2,1),(1,1),(0,0)], [(2,2),(2,1),(1,1),(1,0),(0,0)], [(2,2),(2,1),(2,0),(0,1),(0,0)], [(2,2),(2,1),(1,0),(0,0)], [(2,2),(1,1),(0,1),(0,0)], [(2,2),(1,1),(0,0)], [(2,2),(1,1),(1,0),(0,0)].
Square array A(n,k) begins:
  1, 1,    1,        1,             1,                   1, ...
  1, 1,    3,       13,            75,                 541, ...
  1, 1,   13,      409,         23917,             2244361, ...
  1, 1,   63,    16081,      10681263,         14638956721, ...
  1, 1,  321,   699121,    5552351121,     117029959485121, ...
  1, 1, 1683, 32193253, 3147728203035, 1050740615666453461, ...
		

Crossrefs

Columns: A000012 (k=0 and k=1), A001850 (k=2), A126086 (k=3), A263064 (k=4), A263065 (k=5), A263066 (k=6), A263067 (k=7), A263068 (k=8), A263069 (k=9), A263070 (k=10).
Rows: A000012 (n=0), A000670 (n=1), A055203 (n=2), A062208 (n=3), A062205 (n=4), A263061 (n=5), A263062 (n=6), A062204 (n=7), A263063 (n=8), A263071 (n=9), A263072 (n=10).
Main diagonal: A262810.

Programs

  • Maple
    A:= (n, k)-> add(add((-1)^i*binomial(j, i)*
         binomial(j-i, n)^k, i=0..j), j=0..k*n):
    seq(seq(A(n, d-n), n=0..d), d=0..10);
  • Mathematica
    A[, 0] =  1; A[n, k_] := Sum[Sum[(-1)^i*Binomial[j, i]*Binomial[j - i, n]^k, {i, 0, j}], {j, 0, k*n}];
    Table[Table[A[n, d - n], {n, 0, d}], {d, 0, 10}] // Flatten (* Jean-François Alcover, Jul 22 2016, after Alois P. Heinz *)
  • PARI
    T(n,k) = {my(m=n*k); sum(j=0, m, binomial(j,n)^k*sum(i=j, m, (-1)^(i-j)*binomial(i, j)))} \\ Andrew Howroyd, Jan 23 2020

Formula

A(n,k) = Sum_{j=0..k*n} Sum_{i=0..j} (-1)^i*C(j,i)*C(j-i,n)^k.
A(n,k) = Sum_{i >= 0} binomial(i,n)^k/2^(i+1). - Peter Bala, Jan 30 2018
A(n,k) = Sum_{j=0..n*k} binomial(j,n)^k * Sum_{i=j..n*k} (-1)^(i-j) * binomial(i,j). - Andrew Howroyd, Jan 23 2020

A181197 Number of 3 X n matrices containing a permutation of 1..3*n in increasing order rowwise, columnwise and (downwards) antidiagonally.

Original entry on oeis.org

1, 1, 4, 29, 290, 3532, 49100, 750325, 12310294, 213446666, 3868253164, 72686739116, 1407643591804, 27964937748724, 567853691242796, 11751537336221989, 247263499985110046, 5279409371079693454, 114199628255736623996, 2499214354674134770354
Offset: 1

Views

Author

R. H. Hardin, Oct 10 2010

Keywords

Comments

Row 3 of A181196.
Equivalently, the number of "truncated shifted standard Young tableaux" of shape ; in other words, if we shift the middle row to the right by one unit and the bottom row to the right by two units, we require that the resulting diagram be increasing as we read down or to the right.
To count these tableaux, observe that if we put the entry 2n + 2 + k in the last position of the second row, the bottom row must end with the entries 2n + 3 + k, ..., 3n. The remaining figure can be filled in arbitrarily; it is a shifted Young diagram of shape . Now apply the hook-length formula for shifted Young tableaux. (This argument is due to Greta Panova.)
a(n) is also the number of maximum packings of pattern
[5 6]
[3 4]
[1 2] in column-strict arrays of size 3 X n+1. - Ran Pan, Apr 13 2015
a(n) is also the number of standard Young tableaux of shape (n,n,n) (French notation) such that for any element T(i,j) in the tableau T, its upper element T(i+1,j) is larger than its right element T(i,j+1). - Ran Pan, Apr 13 2015

Examples

			All four 3 X 3 examples:
1..2..3....1..2..3....1..2..4....1..2..4
4..5..6....4..5..7....3..5..6....3..5..7
7..8..9....6..8..9....7..8..9....6..8..9
		

Crossrefs

Row n=3 of A227578. - Alois P. Heinz, Jul 17 2013

Programs

  • Maple
    a:= n-> `if`(n<2, 1, add(((2*n+k-1)!*(n-k)*(n-k-1)) /
             (n!*(n-1)!*k!*(2*n-1)*(n+k)*(n+k-1)), k=0..n-2)):
    seq(a(n), n=1..30);  # Alois P. Heinz, Jul 01 2012
  • Mathematica
    Flatten[{1,Table[Sum[((2*n+k-1)!*(n-k)*(n-k-1))/(n!*(n-1)!*k!*(2*n-1)*(n+k)*(n+k-1)),{k,0,n-2}],{n,2,20}]}] (* Vaclav Kotesovec, Jul 21 2013 *)

Formula

a(n) = Sum_{k=0..n-2} ((2n+k-1)!*(n-k)*(n-k-1)) / (n!*(n-1)!*k!*(2n-1) * (n+k)*(n+k-1)) for n>=2, a(1) = 1.
Recurrence: (2*n-1)*(7*n-13)*n^2*a(n) = 2*(182*n^4 - 1185*n^3 + 2722*n^2 - 2625*n + 900)*a(n-1) + 3*(2*n-5)*(3*n-5)*(3*n-4)*(7*n-6)*a(n-2). - Vaclav Kotesovec, Jul 21 2013
a(n) ~ 3^(3*n+1/2)/(64*Pi*n^4). - Vaclav Kotesovec, Jul 21 2013

Extensions

Formula and comments from Joel B. Lewis, Jul 25 2011

A059231 Number of different lattice paths running from (0,0) to (n,0) using steps from S = {(k,k) or (k,-k): k positive integer} that never go below the x-axis.

Original entry on oeis.org

1, 1, 5, 29, 185, 1257, 8925, 65445, 491825, 3768209, 29324405, 231153133, 1841801065, 14810069497, 120029657805, 979470140661, 8040831465825, 66361595715105, 550284185213925, 4582462506008253, 38306388126997785, 321327658068506121, 2703925940081270205
Offset: 0

Views

Author

Wenjin Woan, Jan 20 2001

Keywords

Comments

If y = x*A(x) then 4*y^2 - (1 + 3*x)*y + x = 0 and x = y*(1 - 4*y) / (1 - 3*y). - Michael Somos, Sep 28 2003
a(n) = A059450(n, n). - Michael Somos, Mar 06 2004
The Hankel transform of this sequence is 4^binomial(n+1,2). - Philippe Deléham, Oct 29 2007
a(n) is the number of Schroder paths of semilength n in which there are no (2,0)-steps at level 0 and at a higher level they come in 3 colors. Example: a(2)=5 because we have UDUD, UUDD, UBD, UGD, and URD, where U=(1,1), D=(1,-1), while B, G, and R are, respectively, blue, green, and red (2,0)-steps. - Emeric Deutsch, May 02 2011
Shifts left when INVERT transform applied four times. - Benedict W. J. Irwin, Feb 02 2016

Examples

			a(3) = 29 since the top row of Q^2 = (5, 8, 16, 0, 0, 0, ...), and 5 + 8 + 16 = 29.
		

Crossrefs

Row sums of A086873.
Column k=2 of A227578. - Alois P. Heinz, Jul 17 2013

Programs

  • Maple
    gf := (1+3*x-sqrt(9*x^2-10*x+1))/(8*x): s := series(gf, x, 100): for i from 0 to 50 do printf(`%d,`,coeff(s, x, i)) od:
    A059231_list := proc(n) local j, a, w; a := array(0..n); a[0] := 1;
    for w from 1 to n do a[w] := a[w-1]+4*add(a[j]*a[w-j-1],j=1..w-1) od;
    convert(a, list) end: A059231_list(20); # Peter Luschny, May 19 2011
  • Mathematica
    Join[{1},Table[-I 3^n/2LegendreP[n,-1,5/3],{n,40}]] (* Harvey P. Dale, Jun 09 2011 *)
    Table[Hypergeometric2F1[-n, 1 - n, 2, 4], {n, 0, 22}] (* Arkadiusz Wesolowski, Aug 13 2012 *)
  • PARI
    {a(n) = if( n<0, 0, polcoeff( (1 + 3*x - sqrt(1 - 10*x + 9*x^2 + x^2 * O(x^n))) / (8*x), n))}; /* Michael Somos, Sep 28 2003 */
    
  • PARI
    {a(n) = if( n<0, 0, n++; polcoeff( serreverse( x * (1 - 4*x) / (1 - 3*x) + x * O(x^n)), n))}; /* Michael Somos, Sep 28 2003 */
    
  • Sage
    # Algorithm of L. Seidel (1877)
    def A059231_list(n) :
        D = [0]*(n+2); D[1] = 1
        R = []; b = False; h = 1
        for i in range(2*n) :
            if b :
                for k in range(1, h, 1) : D[k] += 2*D[k+1]
            else :
                for k in range(h, 0, -1) : D[k] += 2*D[k-1]
                h += 1
            b = not b
            if b : R.append(D[1])
        return R
    A059231_list(23)  # Peter Luschny, Oct 19 2012

Formula

a(n) = Sum_{k=0..n} 4^k*N(n, k) where N(n, k) = (1/n)*binomial(n, k)*binomial(n, k+1) are the Narayana numbers (A001263). - Benoit Cloitre, May 10 2003
a(n) = 3^n/2*LegendreP(n, -1, 5/3). - Vladeta Jovovic, Sep 17 2003
G.f.: (1 + 3*x - sqrt(1 - 10*x + 9*x^2)) / (8*x) = 2 / (1 + 3*x + sqrt(1 - 10*x + 9*x^2)). - Michael Somos, Sep 28 2003
a(n) = Sum_{k=0..n} A088617(n, k)*4^k*(-3)^(n-k). - Philippe Deléham, Jan 21 2004
With offset 1: a(1)=1, a(n) = -3*a(n-1) + 4*Sum_{i=1..n-1} a(i)*a(n-i). - Benoit Cloitre, Mar 16 2004
D-finite with recurrence a(n) = (5(2n-1)a(n-1) - 9(n-2)a(n-2))/(n+1) for n>=2; a(0)=a(1)=1. - Emeric Deutsch, Mar 20 2004
Moment representation: a(n)=(1/(8*Pi))*Int(x^n*sqrt(-x^2+10x-9)/x,x,1,9)+(3/4)*0^n. - Paul Barry, Sep 30 2009
a(n) = upper left term in M^n, M = the production matrix:
1, 1
4, 4, 4
1, 1, 1, 1
4, 4, 4, 4, 4
1, 1, 1, 1, 1, 1
... - Gary W. Adamson, Jul 08 2011
a(n) is the sum of top row terms of Q^(n-1), where Q = the following infinite square production matrix:
1, 4, 0, 0, 0, ...
1, 1, 4, 0, 0, ...
1, 1, 1, 4, 0, ...
1, 1, 1, 1, 4, ...
... - Gary W. Adamson, Aug 23 2011
G.f.: (1+3*x-sqrt(9*x^2-10*x+1))/(8*x)=(1+3*x -G(0))/(4*x) ; G(k)= 1+x*3-x*4/G(k+1); (continued fraction, 1-step ). - Sergei N. Gladkovskii, Jan 05 2012
a(n) ~ sqrt(2)*3^(2*n+1)/(8*sqrt(Pi)*n^(3/2)). - Vaclav Kotesovec, Oct 11 2012
a(n) = A127846(n) for n>0. - Philippe Deléham, Apr 03 2013
0 = a(n)*(+81*a(n+1) - 225*a(n+2) + 36*a(n+3)) + a(n+1)*(+45*a(n+1) + 82*a(n+2) - 25*a(n+3)) + a(n+2)*(+5*a(n+2) + a(n+3)) for all n>=0. - Michael Somos, Aug 25 2014
G.f.: 1/(1 - x/(1 - 4*x/(1 - x/(1 - 4*x/(1 - x/(1 - ...)))))), a continued fraction. - Ilya Gutkovskiy, Aug 10 2017

A263159 Number A(n,k) of lattice paths starting at {n}^k and ending when k or any component equals 0, using steps that decrement one or more components by one; square array A(n,k), n>=0, k>=0, read by antidiagonals.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 7, 13, 1, 1, 1, 15, 157, 63, 1, 1, 1, 31, 2101, 5419, 321, 1, 1, 1, 63, 32461, 717795, 220561, 1683, 1, 1, 1, 127, 580693, 142090291, 328504401, 9763807, 8989, 1, 1, 1, 255, 11917837, 39991899123, 944362553521, 172924236255, 454635973, 48639, 1, 1
Offset: 0

Views

Author

Alois P. Heinz, Oct 11 2015

Keywords

Examples

			Square array A(n,k) begins:
  1, 1,    1,       1,            1,                1, ...
  1, 1,    3,       7,           15,               31, ...
  1, 1,   13,     157,         2101,            32461, ...
  1, 1,   63,    5419,       717795,        142090291, ...
  1, 1,  321,  220561,    328504401,     944362553521, ...
  1, 1, 1683, 9763807, 172924236255, 7622403922836151, ...
		

Crossrefs

Rows n=0-1 give: A000012, A255047.
Main diagonal gives A263160.

Programs

  • Maple
    s:= proc(n) option remember; `if`(n=0, {[]},
          map(x-> [[x[], 0], [x[], 1]][], s(n-1)))
        end:
    b:= proc(l) option remember; `if`(l=[] or l[1]=0, 1,
           add((p-> `if`(p[1]<0, 0, `if`(p[1]=0, 1, b(p)))
           )(sort(l-x)), x=s(nops(l)) minus {[0$nops(l)]}))
        end:
    A:= (n, k)-> b([n$k]):
    seq(seq(A(n,d-n), n=0..d), d=0..10);
  • Mathematica
    g[k_] := Table[Reverse[IntegerDigits[n, 2]][[;;k]], {n, 2^k+1, 2^(k+1)-1}];
    b[l_] := b[l] = If[l[[1]] == 0, 1, Sum[b[Sort[l - h]], {h, g[k]}]];
    a[n_, k_] := If[n == 0 || k == 0 || k == 1, 1, b[Table[n, {k}]]];
    Table[a[n-k, k], {n, 0, 10}, {k, n, 0, -1}] // Flatten (* Jean-François Alcover, Apr 25 2020, after Alois P. Heinz in A115866 *)

A229142 Number A(n,k) of lattice paths from {n}^k to {0}^k using steps that decrement one component or all components by 1; square array A(n,k), n>=0, k>=0, read by antidiagonals.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 7, 13, 1, 1, 1, 25, 115, 63, 1, 1, 1, 121, 2641, 2371, 321, 1, 1, 1, 721, 114121, 392641, 54091, 1683, 1, 1, 1, 5041, 7489441, 169417921, 67982041, 1307377, 8989, 1, 1, 1, 40321, 681120721, 137322405361, 308238414121, 12838867105, 32803219, 48639, 1, 1
Offset: 0

Views

Author

Alois P. Heinz, Sep 23 2013

Keywords

Comments

Column k is the diagonal of the rational function 1 / (1 - Sum_{j=1..k} x_j - Product_{j=1..k} x_j) for k>1. - Seiichi Manyama, Jul 10 2020

Examples

			A(1,3) = 3*2+1 = 7:
          (0,1,1)-(0,0,1)
         /       X       \
  (1,1,1)-(1,0,1) (0,1,0)-(0,0,0)
       \ \       X       / /
        \ (1,1,0)-(1,0,0) /
         `---------------´
Square array A(n,k) begins:
  1, 1,    1,       1,           1,               1, ...
  1, 1,    3,       7,          25,             121, ...
  1, 1,   13,     115,        2641,          114121, ...
  1, 1,   63,    2371,      392641,       169417921, ...
  1, 1,  321,   54091,    67982041,    308238414121, ...
  1, 1, 1683, 1307377, 12838867105, 629799991355641, ...
		

Crossrefs

Rows n=0-1 give: A000012, A038507 (for k>1).
Main diagonal gives: A229267.

Programs

  • Maple
    with(combinat):
    A:= (n,k)-> `if`(k<2, 1, add(multinomial(n+(k-1)*j, n-j, j$k), j=0..n)):
    seq(seq(A(n, d-n), n=0..d), d=0..10);
  • Mathematica
    a[, 0] = a[, 1] = 1; a[n_, k_] := Sum[Product[Binomial[n+j*m, m], {j, 0, k-1}], {m, 0, n}]; Table[a[n-k, k], {n, 0, 10}, {k, n, 0, -1}] // Flatten (* Jean-François Alcover, Dec 11 2013 *)

Formula

A(n,k) = Sum_{j=0..n} multinomial(n+(k-1)*j; n-j, {j}^k) for k>1, A(n,0) = A(n,1) = 1.
G.f. of column k: Sum_{j>=0} (k*j)!/j!^k * x^j / (1-x)^(k*j+1). for k>1. - Seiichi Manyama, Jul 10 2020

A181196 T(n,k) = number of n X k matrices containing a permutation of 1..n*k in increasing order rowwise, columnwise, diagonally and (downwards) antidiagonally.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 5, 4, 1, 1, 1, 14, 29, 8, 1, 1, 1, 42, 290, 169, 16, 1, 1, 1, 132, 3532, 6392, 985, 32, 1, 1, 1, 429, 49100, 352184, 141696, 5741, 64, 1, 1, 1, 1430, 750325, 25097600, 36372976, 3142704, 33461, 128, 1, 1, 1, 4862, 12310294
Offset: 1

Views

Author

R. H. Hardin, Oct 10 2010

Keywords

Comments

Table starts:
.1.1...1......1..........1..............1...................1
.1.1...2......5.........14.............42.................132
.1.1...4.....29........290...........3532...............49100
.1.1...8....169.......6392.........352184............25097600
.1.1..16....985.....141696.......36372976.........14083834704
.1.1..32...5741....3142704.....3777546912.......8092149471168
.1.1..64..33461...69705920...392658046912....4673805856338368
.1.1.128.195025.1546100352.40820345224064.2702482348019033600

Examples

			All solutions for 3 X 4:
..1..2..3..4....1..2..3..4....1..2..3..4....1..2..3..4....1..2..3..4
..5..6..7..8....5..6..7..9....5..6..7.10....5..6..8..9....5..6..8.10
..9.10.11.12....8.10.11.12....8..9.11.12....7.10.11.12....7..9.11.12
...
..1..2..3..6....1..2..3..6....1..2..3..6....1..2..3..6....1..2..3..6
..4..5..7..8....4..5..7..9....4..5..7.10....4..5..8..9....4..5..8.10
..9.10.11.12....8.10.11.12....8..9.11.12....7.10.11.12....7..9.11.12
...
..1..2..4..6....1..2..4..6....1..2..4..6....1..2..4..6....1..2..4..6
..3..5..7..8....3..5..7..9....3..5..7.10....3..5..8..9....3..5..8.10
..9.10.11.12....8.10.11.12....8..9.11.12....7.10.11.12....7..9.11.12
...
..1..2..3..5....1..2..3..5....1..2..3..5....1..2..3..5....1..2..3..5
..4..6..7..8....4..6..7..9....4..6..7.10....4..6..8..9....4..6..8.10
..9.10.11.12....8.10.11.12....8..9.11.12....7.10.11.12....7..9.11.12
...
..1..2..4..5....1..2..4..5....1..2..4..5....1..2..4..5....1..2..4..5
..3..6..7..8....3..6..7..9....3..6..7.10....3..6..8..9....3..6..8.10
..9.10.11.12....8.10.11.12....8..9.11.12....7.10.11.12....7..9.11.12
...
..1..2..3..7....1..2..3..7....1..2..4..7....1..2..4..7
..4..5..8..9....4..5..8.10....3..5..8..9....3..5..8.10
..6.10.11.12....6..9.11.12....6.10.11.12....6..9.11.12
		

Crossrefs

Rows n=1-5 give: A000012, A000108, A181197, A181198, A181199.
Columns 1+2, 3-8 give: A000012, A011782, A001653, A181192, A181193, A181194, A181195.
A227578 is a similar but different array.

Programs

  • Maple
    b:= proc(l) option remember; local n; n:= nops(l);
          `if`({l[]}={0}, 1, add(`if`((i=1 or l[i-1]<=l[i]) and l[i]>
          `if`(i=n, 0, l[i+1]), b(subsop(i=l[i]-1, l)), 0), i=1..n))
        end:
    T:= (n,k)-> b([n$k]):
    seq(seq(T(n, 1+d-n), n=1..d), d=1..12);  # Alois P. Heinz, Jul 24 2012
  • Mathematica
    b[l_List] := b[l] = With[{n = Length[l]}, If[Union[l] == {0}, 1, Sum[If[(i == 1 || l[[i-1]] <= l[[i]]) && l[[i]] > If[i == n, 0, l[[i+1]]], b[ReplacePart[l, i -> l[[i]]-1]], 0], {i, 1, n}]]]; T[n_, k_] := b[Array[n&, k]]; Table[Table[T[n, 1+d-n], {n, 1, d}], {d, 1, 12}] // Flatten (* Jean-François Alcover, Mar 06 2015, after Alois P. Heinz *)

Formula

Empirical column 1: a(n) = a(n-1).
Empirical column 2: a(n) = a(n-1).
Empirical column 3: a(n) = 2*a(n-1).
Empirical column 4: a(n) = 6*a(n-1)-a(n-2).
Empirical column 5: a(n) = 24*a(n-1)-40*a(n-2)-8*a(n-3).
Empirical column 6: a(n) = 120*a(n-1)-1672*a(n-2)+544*a(n-3)-6672*a(n-4) +256*a(n-5).
Empirical column 7: a(n) = 720*a(n-1) -84448*a(n-2) +1503360*a(n-3) -17912224*a(n-4) -318223104*a(n-5) +564996096*a(n-6) +270471168*a(n-7) -11373824*a(n-8) +65536*a(n-9).

A229345 Number A(n,k) of lattice paths from {n}^k to {0}^k using steps that decrement one component or all components by the same positive integer; square array A(n,k), n>=0, k>=0, read by antidiagonals.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 3, 2, 1, 1, 7, 22, 4, 1, 1, 25, 248, 188, 8, 1, 1, 121, 6506, 11380, 1712, 16, 1, 1, 721, 292442, 2359348, 577124, 16098, 32, 1, 1, 5041, 19450082, 1088626684, 991365512, 30970588, 154352, 64, 1
Offset: 0

Views

Author

Alois P. Heinz, Sep 24 2013

Keywords

Examples

			A(2,2) = 22: [(2,2),(1,1),(0,0)], [(2,2),(1,1),(0,1),(0,0)], [(2,2),(1,1),(1,0),(0,0)], [(2,2),(0,0)], [(2,2),(1,2),(0,1),(0,0)], [(2,2),(1,2),(0,2),(0,1),(0,0)], [(2,2),(1,2),(0,2),(0,0)], [(2,2),(1,2),(1,1),(0,0)], [(2,2),(1,2),(1,1),(0,1),(0,0)], [(2,2),(1,2),(1,1),(1,0),(0,0)], [(2,2),(1,2),(1,0),(0,0)], [(2,2),(0,2),(0,1),(0,0)], [(2,2),(0,2),(0,0)], [(2,2),(2,1),(1,0),(0,0)], [(2,2),(2,1),(1,1),(0,0)], [(2,2),(2,1),(1,1),(0,1),(0,0)], [(2,2),(2,1),(1,1),(1,0),(0,0)], [(2,2),(2,1),(0,1),(0,0)], [(2,2),(2,1),(2,0),(1,0),(0,0)], [(2,2),(2,1),(2,0),(0,0)], [(2,2),(2,0),(1,0),(0,0)], [(2,2),(2,0),(0,0)].
Square array A(n,k) begins:
  1,  1,     1,        1,            1,                 1, ...
  1,  1,     3,        7,           25,               121, ...
  1,  2,    22,      248,         6506,            292442, ...
  1,  4,   188,    11380,      2359348,        1088626684, ...
  1,  8,  1712,   577124,    991365512,     4943064622568, ...
  1, 16, 16098, 30970588, 453530591824, 25162900228200976, ...
		

Crossrefs

Columns k=0-3 give: A000012, A011782, A132595(n+1), A229482.
Rows n=0-2 give: A000012, A038507 (for k>1), A229465.
Main diagonal gives: A229346.

Programs

  • Maple
    b:= proc(l) option remember; local m; m:= nops(l);
          `if`(m=0 or l[m]=0, 1,
          `if`(m>1, add(b(l-[j$m]), j=1..l[1]), 0)+
          add(add(b(sort(subsop(i=l[i]-j, l))), j=1..l[i]), i=1..m))
        end:
    A:= (n, k)-> b([n$k]):
    seq(seq(A(n, d-n), n=0..d), d=0..10);  # Alois P. Heinz, Sep 24 2013
  • Mathematica
    b[l_] := b[l] = With[{m = Length[l]}, If[m == 0 || l[[m]] == 0, 1, If[m > 1, Sum[b[l - Array[j&, m]], {j, 1, l[[1]]}],  0] + Sum[Sum[b[Sort[ReplacePart[l, i -> l[[i]] - j]]], {j, 1, l[[i]]}], {i, 1, m}]]]; a[n_, k_] := b[Array[n&, k]]; Table[Table[a[n, d-n], {n, 0, d}], {d, 0, 10}] // Flatten (* Jean-François Alcover, Dec 16 2013, translated from Maple *)

A227579 Number of lattice paths from {n}^n to {0}^n using steps that decrement one component such that for each point (p_1,p_2,...,p_n) we have p_1<=p_2<=...<=p_n.

Original entry on oeis.org

1, 1, 5, 290, 456033, 36470203156, 237791136700913751, 184570140930218389159747070, 23408169635197679203800470649923362577, 637028433009539403532335279417025047587902906655768, 4725612998324981086891784010767387049970117446517002416810380479702
Offset: 0

Views

Author

Alois P. Heinz, Jul 16 2013

Keywords

Examples

			a(2) = 5: [(2,2),(0,2),(0,0)], [(2,2),(0,2),(0,1),(0,0)], [(2,2),(1,2),(0,2),(0,0)], [(2,2),(1,2),(0,2),(0,1),(0,0)], [(2,2),(1,2),(1,1),(0,1),(0,0)].
		

Crossrefs

Main diagonal of A227578.

Programs

  • Maple
    b:= proc(l) option remember; `if`(l[-1]=0, 1, add(add(b(subsop(
          i=j, l)), j=`if`(i=1, 0, l[i-1])..l[i]-1), i=1..nops(l)))
        end:
    a:= n-> `if`(n=0, 1, b([n$n])):
    seq(a(n), n=0..9);
  • Mathematica
    b[l_] := b[l] = If[l[[-1]] == 0, 1, Sum[Sum[b[ReplacePart[l, i -> j]], {j, If[i == 1, 0, l[[i - 1]]], l[[i]] - 1}], {i, 1, Length[l]}]];
    a[n_] := If[n == 0, 1, b[Table[n, {n}]]];
    a /@ Range[0, 9] (* Jean-François Alcover, Jan 03 2021, after Alois P. Heinz *)

A227580 Number of lattice paths from {n}^3 to {0}^3 using steps that decrement one component such that for each point (p_1,p_2,p_3) we have p_1<=p_2<=p_3.

Original entry on oeis.org

1, 1, 14, 290, 7680, 238636, 8285506, 312077474, 12509563082, 526701471002, 23076216957520, 1044813920439200, 48630132961189400, 2317337976558074760, 112689430179458971738, 5577655817793682738378, 280392321290875174774106, 14290804691034216155457274
Offset: 0

Views

Author

Alois P. Heinz, Jul 16 2013

Keywords

Examples

			a(2) = 14: [(2,2,2),(0,2,2),(0,0,2),(0,0,0)], [(2,2,2),(0,2,2),(0,0,2),(0,0,1),(0,0,0)], [(2,2,2),(0,2,2),(0,1,2),(0,0,2),(0,0,0)], [(2,2,2),(0,2,2),(0,1,2),(0,0,2),(0,0,1),(0,0,0)], [(2,2,2),(0,2,2),(0,1,2),(0,1,1),(0,0,1),(0,0,0)], [(2,2,2),(1,2,2),(0,2,2),(0,0,2),(0,0,0)], [(2,2,2),(1,2,2),(0,2,2),(0,0,2),(0,0,1),(0,0,0)], [(2,2,2),(1,2,2),(0,2,2),(0,1,2),(0,0,2),(0,0,0)], [(2,2,2),(1,2,2),(0,2,2),(0,1,2),(0,0,2),(0,0,1),(0,0,0)], [(2,2,2),(1,2,2),(0,2,2),(0,1,2),(0,1,1),(0,0,1),(0,0,0)], [(2,2,2),(1,2,2),(1,1,2),(0,1,2),(0,0,2),(0,0,0)], [(2,2,2),(1,2,2),(1,1,2),(0,1,2),(0,0,2),(0,0,1),(0,0,0)], [(2,2,2),(1,2,2),(1,1,2),(0,1,2),(0,1,1),(0,0,1),(0,0,0)], [(2,2,2),(1,2,2),(1,1,2),(1,1,1),(0,1,1),(0,0,1),(0,0,0)].
		

Crossrefs

Column k=3 of A227578.

Programs

  • Maple
    a:= proc(n) option remember; `if`(n<3, [1, 1, 14][n+1],
          ((n+1)*(665*n^3-1433*n^2+980*n-204) *a(n-1)
           -(n-2)*(1615*n^3-3218*n^2+1521*n-342) *a(n-2)
           +192*(5*n-1)*(n-3)*(n-2)^2 *a(n-3)) /
           (2*(n+2)*(5*n-6)*(n+1)^2))
        end:
    seq(a(n), n=0..30);
  • Mathematica
    b[l_] := b[l] = If[l[[-1]] == 0, 1, Sum[Sum[b[ReplacePart[l, i -> j]], {j, If[i == 1, 0, l[[i-1]]], l[[i]] - 1}], {i, 1, Length[l]}]];
    a[n_] := b[Array[n&, 3]];
    a /@ Range[0, 30] (* Jean-François Alcover, Dec 20 2020, after Alois P. Heinz in A227578 *)

Formula

a(n) ~ 2^(6*n+10)/(sqrt(3)*Pi*(5*n)^4). - Vaclav Kotesovec, Jul 18 2013
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