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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A257505 Square array A(row,col): A(row,1) = A256450(row-1), and for col > 1, A(row,col) = A255411(A(row,col-1)); Dispersion of factorial base shift A255411.

Original entry on oeis.org

1, 4, 2, 18, 12, 3, 96, 72, 16, 5, 600, 480, 90, 22, 6, 4320, 3600, 576, 114, 48, 7, 35280, 30240, 4200, 696, 360, 52, 8, 322560, 282240, 34560, 4920, 2880, 378, 60, 9, 3265920, 2903040, 317520, 39600, 25200, 2976, 432, 64, 10, 36288000, 32659200, 3225600, 357840, 241920, 25800, 3360, 450, 66, 11, 439084800, 399168000, 35925120, 3588480, 2540160, 246240, 28800, 3456, 456, 70, 13
Offset: 1

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Author

Antti Karttunen, Apr 27 2015

Keywords

Comments

The array is read by downward antidiagonals: A(1,1), A(1,2), A(2,1), A(1,3), A(2,2), A(3,1), etc.
In Kimberling's terminology, this array is called the dispersion of sequence A255411 (when started from its first nonzero term, 4). The left column is the complement of that sequence, which is A256450.

Examples

			The top left corner of the array:
   1,   4,  18,   96,   600,   4320,   35280,   322560,   3265920
   2,  12,  72,  480,  3600,  30240,  282240,  2903040,  32659200
   3,  16,  90,  576,  4200,  34560,  317520,  3225600,  35925120
   5,  22, 114,  696,  4920,  39600,  357840,  3588480,  39553920
   6,  48, 360, 2880, 25200, 241920, 2540160, 29030400, 359251200
   7,  52, 378, 2976, 25800, 246240, 2575440, 29352960, 362517120
   8,  60, 432, 3360, 28800, 272160, 2822400, 31933440, 391910400
   9,  64, 450, 3456, 29400, 276480, 2857680, 32256000, 395176320
  10,  66, 456, 3480, 29520, 277200, 2862720, 32296320, 395539200
  11,  70, 474, 3576, 30120, 281520, 2898000, 32618880, 398805120
  13,  76, 498, 3696, 30840, 286560, 2938320, 32981760, 402433920
  14,  84, 552, 4080, 33840, 312480, 3185280, 35562240, 431827200
  15,  88, 570, 4176, 34440, 316800, 3220560, 35884800, 435093120
  17,  94, 594, 4296, 35160, 321840, 3260880, 36247680, 438721920
  19, 100, 618, 4416, 35880, 326880, 3301200, 36610560, 442350720
  20, 108, 672, 4800, 38880, 352800, 3548160, 39191040, 471744000
  21, 112, 690, 4896, 39480, 357120, 3583440, 39513600, 475009920
  23, 118, 714, 5016, 40200, 362160, 3623760, 39876480, 478638720
  ...
		

Crossrefs

Transpose: A257503.
Inverse permutation: A257506.
Row index: A257681, Column index: A257679.
Columns 1-3: A256450, A257692, A257693.
Rows 1-3: A001563, A062119, A130744 (without their initial zero-terms).
Row 4: A213167 (without the initial one).
Row 5: A052571 (without initial zeros).
Cf. also permutations A255565, A255566.
Thematically similar arrays: A035513, A054582, A246279.

Programs

Formula

A(row,1) = A256450(row-1), and for col > 1, A(row,col) = A255411(A(row,col-1)).

Extensions

Formula changed because of the changed starting offset of A256450 - Antti Karttunen, May 30 2016

A322383 Number T(n,k) of entries in the k-th cycles of all permutations of [n] when cycles are ordered by increasing lengths (and increasing smallest elements); triangle T(n,k), n>=1, 1<=k<=n, read by rows.

Original entry on oeis.org

1, 3, 1, 10, 7, 1, 45, 37, 13, 1, 236, 241, 101, 21, 1, 1505, 1661, 896, 226, 31, 1, 10914, 13301, 7967, 2612, 442, 43, 1, 90601, 117209, 78205, 29261, 6441, 785, 57, 1, 837304, 1150297, 827521, 346453, 88909, 14065, 1297, 73, 1, 8610129, 12314329, 9507454, 4338214, 1253104, 234646, 28006, 2026, 91, 1
Offset: 1

Views

Author

Alois P. Heinz, Dec 05 2018

Keywords

Examples

			The 6 permutations of {1,2,3} are:
  (1)     (2)   (3)
  (1)     (2,3)
  (2)     (1,3)
  (3)     (1,2)
  (1,2,3)
  (1,3,2)
so there are 10 elements in the first cycles, 7 in the second cycles and only 1 in the third cycles.
Triangle T(n,k) begins:
      1;
      3,      1;
     10,      7,     1;
     45,     37,    13,     1;
    236,    241,   101,    21,    1;
   1505,   1661,   896,   226,   31,   1;
  10914,  13301,  7967,  2612,  442,  43,  1;
  90601, 117209, 78205, 29261, 6441, 785, 57, 1;
  ...
		

Crossrefs

Row sums give A001563.

Programs

  • Maple
    b:= proc(n, l) option remember; `if`(n=0, add(l[i]*
          x^i, i=1..nops(l)), add(binomial(n-1, j-1)*
          b(n-j, sort([l[], j]))*(j-1)!, j=1..n))
        end:
    T:= n-> (p-> (seq(coeff(p, x, i), i=1..n)))(b(n, [])):
    seq(T(n), n=1..12);
  • Mathematica
    b[n_, l_] := b[n, l] = If[n == 0, l.x^Range[Length[l]], Sum[Binomial[n - 1, j - 1] b[n - j, Sort[Append[l, j]]] (j - 1)!, {j, 1, n}]];
    T[n_] := Rest @ CoefficientList[b[n, {}], x];
    Array[T, 12] // Flatten (* Jean-François Alcover, Mar 03 2020, after Alois P. Heinz *)

A322384 Number T(n,k) of entries in the k-th cycles of all permutations of [n] when cycles are ordered by decreasing lengths (and increasing smallest elements); triangle T(n,k), n>=1, 1<=k<=n, read by rows.

Original entry on oeis.org

1, 3, 1, 13, 4, 1, 67, 21, 7, 1, 411, 131, 46, 11, 1, 2911, 950, 341, 101, 16, 1, 23563, 7694, 2871, 932, 197, 22, 1, 213543, 70343, 26797, 9185, 2311, 351, 29, 1, 2149927, 709015, 275353, 98317, 27568, 5119, 583, 37, 1, 23759791, 7867174, 3090544, 1141614, 343909, 73639, 10366, 916, 46, 1
Offset: 1

Views

Author

Alois P. Heinz, Dec 05 2018

Keywords

Examples

			The 6 permutations of {1,2,3} are:
  (1)     (2) (3)
  (1,2)   (3)
  (1,3)   (2)
  (2,3)   (1)
  (1,2,3)
  (1,3,2)
so there are 13 elements in the first cycles, 4 in the second cycles and only 1 in the third cycles.
Triangle T(n,k) begins:
       1;
       3,     1;
      13,     4,     1;
      67,    21,     7,    1;
     411,   131,    46,   11,    1;
    2911,   950,   341,  101,   16,   1;
   23563,  7694,  2871,  932,  197,  22,  1;
  213543, 70343, 26797, 9185, 2311, 351, 29, 1;
  ...
		

Crossrefs

Row sums give A001563.
T(2n,n) gives A332928.

Programs

  • Maple
    b:= proc(n, l) option remember; `if`(n=0, add(l[-i]*
          x^i, i=1..nops(l)), add(binomial(n-1, j-1)*
          b(n-j, sort([l[], j]))*(j-1)!, j=1..n))
        end:
    T:= n-> (p-> (seq(coeff(p, x, i), i=1..n)))(b(n, [])):
    seq(T(n), n=1..12);
  • Mathematica
    b[n_, l_] := b[n, l] = If[n == 0, Sum[l[[-i]]*x^i, {i, 1, Length[l]}], Sum[Binomial[n-1, j-1]*b[n-j, Sort[Append[l, j]]]*(j-1)!, {j, 1, n}]];
    T[n_] := CoefficientList[b[n, {}], x] // Rest;
    Array[T, 12] // Flatten  (* Jean-François Alcover, Feb 26 2020, after Alois P. Heinz *)

A152818 Array read by antidiagonals: A(n,k) = (k+1)^n*(n+k)!/n!.

Original entry on oeis.org

1, 1, 1, 1, 4, 2, 1, 12, 18, 6, 1, 32, 108, 96, 24, 1, 80, 540, 960, 600, 120, 1, 192, 2430, 7680, 9000, 4320, 720, 1, 448, 10206, 53760, 105000, 90720, 35280, 5040, 1, 1024, 40824, 344064, 1050000, 1451520, 987840, 322560, 40320
Offset: 0

Views

Author

Paul Curtz, Dec 13 2008

Keywords

Comments

A009998/A119502 gives triangle of unreduced coefficients of polynomials defined by A152650/A152656. a(n) gives numerators with denominators n! for each row.
Row 0 is A000142. Row 1 is formed from positive members of A001563. Row 2 is A055533. Column 0 is A000012. Column 1 is formed from positive members of A001787. Column 2 is A006043. Column 3 is A006044. - Omar E. Pol, Jan 06 2009

Examples

			From _Omar E. Pol_, Jan 06 2009: (Start)
Array begins:
  1,    1,      2,        6,         24,          120, ...
  1,    4,     18,       96,        600,         4320, ...
  1,   12,    108,      960,       9000,        90720, ...
  1,   32,    540,     7680,     105000,      1451520, ...
  1,   80,   2430,    53760,    1050000,     19595520, ...
  1,  192,  10206,   344064,    9450000,    235146240, ...
  1,  448,  40824,  2064384,   78750000,   2586608640, ...
  1, 1024, 157464, 11796480,  618750000,  26605117440, ...
  1, 2304, 590490, 64880640, 4640625000, 259399895040, ... (End)
Antidiagonal triangle:
  1;
  1,   1;
  1,   4,     2;
  1,  12,    18,     6;
  1,  32,   108,    96,     24;
  1,  80,   540,   960,    600,   120;
  1, 192,  2430,  7680,   9000,  4320,   720;
  1, 448, 10206, 53760, 105000, 90720, 35280, 5040;
		

Crossrefs

Programs

  • Magma
    A152818:= func< n,k | (k+1)^(n-k)*Factorial(k)*Binomial(n,k) >;
    [A152818(n,k): k in [0..n], n in [0..12]]; // G. C. Greubel, Apr 10 2023
  • Mathematica
    len= 45; m= 1 + Ceiling[Sqrt[len]]; Sort[Flatten[#, 1] &[MapIndexed[ {(2 +#2[[1]]^2 +(#2[[2]] -1)*#2[[2]] +#2[[1]]*(2*#2[[2]] -3))/ 2, #1}&, Table[(k+1)^n*(n+k)!/n!, {n,0,m}, {k,0,m}], {2}]]][[All, 2]][[1 ;; len]] (* From Jean-François Alcover, May 27 2011 *)
    T[n_, k_]:= (k+1)^(n-k)*k!*Binomial[n, k];
    Table[T[n,k], {n,0,15}, {k,0,n}]//Flatten (* G. C. Greubel, Apr 10 2023 *)
  • PARI
    A(n,k) = (k+1)^n*(n+k)!/n! \\ Charles R Greathouse IV, Sep 10 2016
    
  • Sage
    def A152818_row(n):
        R. = ZZ[]
        P = add((n-k+1)^k*x^(n-k+1)*factorial(n)/factorial(k) for k in (0..n))
        return P.coefficients()
    for n in (0..12): print(A152818_row(n))  # Peter Luschny, May 03 2013
    

Formula

E.g.f. for array as a triangle: exp(x)/(1-t*x*exp(x)) = 1+(1+t)*x+(1+4*t+2*t^2)*x^2/2! + (1+12*t+18*t^2+6*t^3)*x^3/3! + .... E.g.f. is int {z = 0..inf} exp(-z)*F(x,t*z), (x and t chosen sufficiently small for the integral to converge), where F(x,t) = exp(x*(1+t*exp(x))) is the e.g.f. for A154372. - Peter Bala, Oct 09 2011
From Peter Bala, Oct 09 2011: (Start)
From the e.g.f., the row polynomials R(n,t) satisfy the recursion R(n,t) = 1 + t*sum {k = 0..n-1} n!/(k!*(n-k-1)!)*R(n-k-1,t). The polynomials 1/n!*R(n,x) are the polynomials P(n,x) of A152650.
Sum_{k=0..n} T(n, k) = A072597(n) (antidiagonal sums). (End)
From G. C. Greubel, Apr 10 2023: (Start)
T(n, k) = (k+1)^(n-k) * k! * binomial(n, k) (antidiagonal triangle).
Sum_{k=0..n} (-1)^k*T(n, k) = A089148(n). (End)

Extensions

Better definition, extended and edited by Omar E. Pol and N. J. A. Sloane, Jan 05 2009

A001688 4th forward differences of factorial numbers A000142.

Original entry on oeis.org

9, 53, 362, 2790, 24024, 229080, 2399760, 27422640, 339696000, 4536362880, 64988179200, 994447238400, 16190733081600, 279499828608000, 5100017213491200, 98087346669312000, 1983334021853184000, 42063950934061056000, 933754193111900160000
Offset: 0

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Author

Keywords

References

  • N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
  • N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Crossrefs

Programs

  • Mathematica
    Table[(n^4 + 6*n^3 + 17*n^2 + 20*n + 9) n!, {n, 0, 20}] (* T. D. Noe, Aug 09 2012 *)
    Differences[Range[0,30]!,4] (* Harvey P. Dale, Jun 06 2017 *)
  • PARI
    a(n)=if(n<0,0,n!*(n^4 + 6*n^3 + 17*n^2 + 20*n + 9))

Formula

For n>=0 a(n) = n!*(n^4 + 6*n^3 + 17*n^2 + 20*n + 9). - Benoit Cloitre, Jun 10 2004
G.f.: -log(-x+1)+1+2/(x-1)^4*x*(4-3*x+2*x^2). - Simon Plouffe, Master's Thesis, Uqam 1992
E.g.f.: (9 + 8*x + 6*x^2 + x^4)/(1 - x)^5. - Ilya Gutkovskiy, Jan 20 2017
a(n) = (n+5)*a(n-1) - (n-1)*a(n-2) with a(0) = 9 and a(1) = 53. Cf. A095177. - Peter Bala, Jul 22 2021

A067318 Sum of the reflection lengths of all permutations of n letters.

Original entry on oeis.org

0, 1, 7, 46, 326, 2556, 22212, 212976, 2239344, 25659360, 318540960, 4261576320, 61148511360, 937030429440, 15275952518400, 264030355814400, 4823280687052800, 92865738644582400, 1879691760950169600, 39905092126771200000, 886664974825728000000
Offset: 1

Views

Author

H. Nick Hann (nickhann(AT)aol.com), Jan 15 2002

Keywords

Comments

The reflection length of a permutation is the minimum number of transpositions needed to express the permutation.
May also be called the "weight" of the symmetric group S_n.
a(n) is the number of n+1-permutations that have at least 3 cycles. a(n) = Sum_{k=3..n+1} A132393(n+1,k). Cf. A001563 (n-permutations with at least 2 cycles). - Geoffrey Critzer, Dec 01 2013
The number of covering relations in the middle order on S_n. - Bridget Tenner, Jul 11 2025

Examples

			a(3)=7 since the permutations are 1, (12), (13), (23), (12)(13) and (13)(12). The sum of reflection lengths of all elements in S_3 is 0+1+1+1+2+2=7.
The terms satisfy the series: x/(1-x) = x/((1+x)*(1+2*x)*(1+3*x)) + 7*x^2/((1+x)*(1+2*x)*(1+3*x)*(1+4*x)) + 46*x^3/((1+x)*(1+2*x)*(1+3*x)*(1+4*x)*(1+5*x)) + 326*x^4/((1+x)*(1+2*x)*(1+3*x)*(1+4*x)*(1+5*x)*(1+6*x)) + ... - _Paul D. Hanna_, Aug 28 2012
		

References

  • N. Hann, Average Weight of a Random Permutation, preprint, 2002. [Apparently unpublished]

Crossrefs

Programs

  • Maple
    ZL :=[S, {S = Set(Cycle(Z),3 <= card)}, labelled]: seq(combstruct[count](ZL, size=n), n=2..22); # Zerinvary Lajos, Mar 25 2008
  • Mathematica
    a[n_] := n!*(n - HarmonicNumber[n]); Table[a[n], {n, 1, 21}](* Jean-François Alcover, Feb 10 2012 *)
    nn=22;Drop[Range[0,nn]!CoefficientList[Series[1/(1-x)-1-Log[1/(1-x)]-Log[1/(1-x)]^2/2!,{x,0,nn}],x],2] (* Geoffrey Critzer, Dec 01 2013 *)
  • Maxima
    A067318(n):=n*n! - abs(stirling1(n+1, 2))$
    makelist(A067318(n),n,1,30); /* Martin Ettl, Nov 03 2012 */
  • PARI
    {a(n)=if(n==0,0,if(n==1, 1, 1-polcoeff(sum(k=1, n-1, a(k)*x^k/prod(j=1, k+2, (1+j*x+x*O(x^n)) ) ), n)))} /* Paul D. Hanna, Aug 28 2012 */
    

Formula

a(n) = n!*(0/1+1/2+...+(n-1)/n) = n!*(n - H_n), where H_n = Sum_{k=1..n} 1/k; a(1) = 0, a(2) = 1, a(n) = n*a(n-1) + (n-1)*(n-1)!.
a(n) = n*n! - abs(stirling1(n+1, 2)) (cf. A000254). E.g.f.: (x+(1-x)*log(1-x))/(1-x)^2. - Vladeta Jovovic, Feb 01 2003
a(n) = T(n, n-1) for the triangle read by rows: [0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, ...] DELTA [1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, ...] where DELTA is the operator defined in A084938. - Philippe Deléham, Nov 30 2003
G.f.: x/(1-x) = Sum_{n>=1} a(n)*x^n/Product_{k=1..n+2} (1+k*x). - Paul D. Hanna, Aug 28 2012
a(n) = A062119(n) - A001705(n-1). - Anton Zakharov, Sep 22 2016

Extensions

Definition and example edited by Bridget Tenner, Jul 11 2025

A001689 5th forward differences of factorial numbers A000142.

Original entry on oeis.org

44, 309, 2428, 21234, 205056, 2170680, 25022880, 312273360, 4196666880, 60451816320, 929459059200, 15196285843200, 263309095526400, 4820517384883200, 92987329455820800, 1885246675183872000, 40080616912207872000, 891690242177839104000
Offset: 0

Views

Author

Keywords

References

  • N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
  • N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Crossrefs

Programs

  • Mathematica
    Differences[Table[n!, {n, 0, 25}], 5] (* T. D. Noe, Aug 09 2012 *)

Formula

a(n) = (n^5 + 10*n^4 + 45*n^3 + 100*n^2 + 109*n + 44)*n! - Mitch Harris, Jul 10 2008
E.g.f.: (44 + 45*x + 20*x^2 + 10*x^3 + x^5)/(1 - x)^6. - Ilya Gutkovskiy, Jan 20 2017
a(n) = (n+6)*a(n-1) - (n-1)*a(n-2) with a(0) = 44 and a(1) = 309. Cf. A096307. - Peter Bala, Jul 22 2021

A061206 a(n) = total number of occurrences of the consecutive pattern 1324 in all permutations of [n+3].

Original entry on oeis.org

1, 10, 90, 840, 8400, 90720, 1058400, 13305600, 179625600, 2594592000, 39956716800, 653837184000, 11333177856000, 207484333056000, 4001483566080000, 81096733605888000, 1723305589125120000, 38318206628782080000, 889833909490606080000, 21543347282404147200000
Offset: 1

Views

Author

Melvin J. Knight (knightmj(AT)juno.com), May 30 2001

Keywords

Comments

a(n) is the number of sequences of n+3 balls colored with at most n colors such that exactly four balls are the same color as some other ball in the sequence. - Jeremy Dover, Sep 27 2017

Examples

			a(4)=840 because 4*(7!)/24 = 4*7*6*5 = 840.
		

Crossrefs

Programs

  • Magma
    [n*Factorial(n+3)/24: n in [1..20]]; // Vincenzo Librandi, Oct 11 2011
    
  • Maple
    a := n -> n!*binomial(-n,4): seq(a(n),n=1..20); # Peter Luschny, Apr 29 2016
  • Mathematica
    Array[# (# + 3)!/24 &, 20] (* or *) Array[#!*Binomial[-#, 4] &, 20] (* Michael De Vlieger, Sep 30 2017 *)
  • PARI
    a(n) = n*(n+3)!/24; \\ Altug Alkan, Oct 08 2017
  • Sage
    [binomial(n,4)*factorial (n-3) for n in range(4, 21)] # Zerinvary Lajos, Jul 07 2009
    

Formula

a(n) = n*(n+3)!/24.
If we define f(n,i,x) = Sum_{k=i..n} Sum_{j=i..k} binomial(k,j)*Stirling1(n,k)*Stirling2(j,i) * x^(k-j), then a(n-3) = (-1)^n*f(n,4,-2), (n >= 4). - Milan Janjic, Mar 01 2009
E.g.f.: x/(1-x)^5. (This was initiated by e-mail exchange with Gary Detlefs.) - Wolfdieter Lang, May 28 2010
a(n) = ((n+4)!/6) * Sum_{k=1..n} (k+2)!/(k+4)!. - Gary Detlefs, Aug 05 2010
a(n) = Sum_{k>0} k * A264173(n+3,k). - Alois P. Heinz, Nov 06 2015
a(n) = n!*binomial(-n,4). - Peter Luschny, Apr 29 2016
From Amiram Eldar, Sep 24 2022: (Start)
Sum_{n>=1} 1/a(n) = 118/3 - 16*e - 4*gamma + 4*Ei(1), where gamma is Euler's constant (A001620) and Ei(1) is the exponential integral at 1 (A091725).
Sum_{n>=1} (-1)^(n+1)/a(n) = 2/3 - 8/e + 4*gamma - 4*Ei(-1), where -Ei(-1) is the negated exponential integral at -1 (A099285). (End)

Extensions

More terms from Jason Earls, Jun 12 2001
Corrected by Zerinvary Lajos, Jul 07 2009
More precise definition from Alois P. Heinz, Nov 06 2015

A229001 Total sum A(n,k) of the k-th powers of lengths of ascending runs in all permutations of [n]; square array A(n,k), n>=0, k>=0, read by antidiagonals.

Original entry on oeis.org

0, 0, 1, 0, 1, 3, 0, 1, 4, 12, 0, 1, 6, 18, 60, 0, 1, 10, 32, 96, 360, 0, 1, 18, 66, 186, 600, 2520, 0, 1, 34, 152, 426, 1222, 4320, 20160, 0, 1, 66, 378, 1110, 2964, 9086, 35280, 181440, 0, 1, 130, 992, 3186, 8254, 22818, 75882, 322560, 1814400
Offset: 0

Views

Author

Alois P. Heinz, Sep 10 2013

Keywords

Examples

			A(3,2) = 32 = 9+5+5+5+5+3 = 3^2+4*(2^2+1^2)+3*1^2: (1,2,3), (1,3,2), (2,1,3), (2,3,1), (3,1,2), (3,2,1).
Square array A(n,k) begins:
:    0,    0,    0,     0,     0,      0,      0, ...
:    1,    1,    1,     1,     1,      1,      1, ...
:    3,    4,    6,    10,    18,     34,     66, ...
:   12,   18,   32,    66,   152,    378,    992, ...
:   60,   96,  186,   426,  1110,   3186,   9846, ...
:  360,  600, 1222,  2964,  8254,  25620,  86782, ...
: 2520, 4320, 9086, 22818, 66050, 214410, 765506, ...
		

Crossrefs

Columns k=0-10 give: A001710(n+1) for n>0, A001563, A228959, A229003, A228994, A228995, A228996, A228997, A228998, A228999, A229000.
Rows n=0-2 give: A000004, A000012, A052548.
Main diagonal gives: A229002.

Programs

  • Maple
    A:= (n, k)-> add(`if`(n=t, 1, n!/(t+1)!*(t*(n-t+1)+1
                 -((t+1)*(n-t)+1)/(t+2)))*t^k, t=1..n):
    seq(seq(A(n, d-n), n=0..d), d=0..12);
  • Mathematica
    A[n_, k_] := Sum[If[n == t, 1, n!/(t + 1)!*(t*(n - t + 1) + 1 - ((t + 1)*(n - t) + 1)/(t + 2))]* t^k, {t, 1, n}]; Table[Table[A[n, d - n], {n, 0, d}], {d, 0, 12}] // Flatten (* Jean-François Alcover, Dec 27 2013, translated from Maple *)

Formula

A(n,k) = Sum_{t=1..n} t^k * A122843(n,t).
For fixed k, A(n,k) ~ n! * n * sum(t>=1, t^k*(t^2+t-1)/(t+2)!) = n! * n * ((Bell(k) - Bell(k+1) + sum(j=0..k, (-1)^j*(2^j*((2*k-j+1)/(j+1))-1) *Bell(k-j)*C(k,j)))*exp(1) - (-1)^k*(2^k-1)), where Bell(k) are Bell numbers A000110. - Vaclav Kotesovec, Sep 12 2013

A061845 Numbers that have one of every digit in some base.

Original entry on oeis.org

2, 11, 15, 19, 21, 75, 78, 99, 108, 114, 120, 135, 141, 147, 156, 177, 180, 198, 201, 210, 216, 225, 228, 694, 698, 714, 722, 738, 742, 894, 898, 954, 970, 978, 990, 1014, 1022, 1054, 1070, 1102, 1110, 1138, 1142, 1178, 1190, 1202, 1210, 1294, 1298, 1334
Offset: 2

Views

Author

Erich Friedman, Jun 23 2001

Keywords

Comments

Also known as pandigital numbers, especially in base 10.

Examples

			Base 3 values are 102_3 = 11, 120_3 = 15, 201_3 = 19, 210_3 = 21.
Triangle begins:
    2;
   11,  15,  19,  21;
   75,  78,  99, 108, 114, 120, 135, 141, 147, 156, 177, 180,  198,  201, ...
  694, 698, 714, 722, 738, 742, 894, 898, 954, 970, 978, 990, 1014, 1022, ...
  ...
		

Crossrefs

Column k=1 gives A049363 (for n>1).
Last elements of rows give A062813.
Cf. A050278, A134640, A001563 (row lengths).

Programs

  • Mathematica
    dtn[ L_, base_ ] := Fold[ base*#1+#2&, 0, L ] f[ n_ ] := Map[ dtn[ #, n ]&, Select[ Permutations[ Range[ 0, n-1 ] ], First[ # ]>0& ] ] Flatten[ Join[ Table[ f[ i ], {i, 2, 5} ] ] ]
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