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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A365673 Array A(n, k) read by ascending antidiagonals. Polygonal number weighted generalized Catalan sequences.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 3, 4, 1, 1, 1, 4, 15, 8, 1, 1, 1, 5, 34, 105, 16, 1, 1, 1, 6, 61, 496, 945, 32, 1, 1, 1, 7, 96, 1385, 11056, 10395, 64, 1, 1, 1, 8, 139, 2976, 50521, 349504, 135135, 128, 1, 1, 1, 9, 190, 5473, 151416, 2702765, 14873104, 2027025, 256, 1
Offset: 0

Views

Author

Peter Luschny, Sep 30 2023

Keywords

Comments

Using polygonal numbers as weights, a recursion for triangles is defined, whose main diagonals represents a family of sequences, which include, among others, the powers of 2, the double factorial of odd numbers, the reduced tangent numbers, and the Euler numbers.
Apart from the edge cases k = 0 and k = n the recursion is T(n, k) = w(n, k) * T(n, k - 1) + T(n - 1, k). T(n, 0) = 1 and T(n, n) = T(n, n-1) if n > 0.
The weights w(n, k) identical to 1 yield the recursion of the Catalan triangle A009766 (with main diagonal the Catalan numbers). Here the polygonal numbers are used as weights in the form w(n, k) = p(s, n - k + 1), where the parameter s is the number of sides of the polygon and p(s, n) = ((s-2) * n^2 - (s-4) * n) / 2, see A317302.

Examples

			Array A(n, k) starts:                            (polygon|diagonal|triangle)
[0] 1, 1, 1,   1,     1,       1,         1, ...  A258837  A000012
[1] 1, 1, 2,   4,     8,      16,        32, ...  A080956  A011782
[2] 1, 1, 3,  15,   105,     945,     10395, ...  A001477  A001147  A001498
[3] 1, 1, 4,  34,   496,   11056,    349504, ...  A000217  A002105  A365674
[4] 1, 1, 5,  61,  1385,   50521,   2702765, ...  A000290  A000364  A060058
[5] 1, 1, 6,  96,  2976,  151416,  11449296, ...  A000326  A126151  A366138
[6] 1, 1, 7, 139,  5473,  357721,  34988647, ...  A000384  A126156  A365672
[7] 1, 1, 8, 190,  9080,  725320,  87067520, ...  A000566  A366150  A366149
[8] 1, 1, 9, 249, 14001, 1322001, 188106489, ...  A000567
           A054556                         A366137
		

Crossrefs

Cf. A009766, A366137 (central diagonal), A317302 (table of polygonal numbers).

Programs

  • Maple
    poly := (s, n) -> ((s - 2) * n^2 - (s - 4) * n) / 2:
    T := proc(s, n, k) option remember; if k = 0 then 1 else if k = n then T(s, n, k-1) else poly(s, n - k + 1) * T(s, n, k - 1) + T(s, n - 1, k) fi fi end:
    for n from 0 to 8 do A := (n, k) -> T(n, k, k): seq(A(n, k), k = 0..9) od;
    # Alternative, using continued fractions:
    A := proc(p, L) local CF, poly, k, m, P, ser;
       poly := (s, n) -> ((s - 2)*n^2 - (s - 4)*n)/2;
       CF := 1 + x;
       for k from 1 to L do
           m := L - k + 1;
           P := poly(p, m);
           CF := 1/(1 - P*x*CF)
       od;
       ser := series(CF, x, L);
       seq(coeff(ser, x, m), m = 0..L-1)
    end:
    for p from 0 to 8 do lprint(A(p, 8)) od;
  • Mathematica
    poly[s_, n_] := ((s - 2) * n^2 - (s - 4) * n) / 2;
    T[s_, n_, k_] := T[s, n, k] = If[k == 0, 1, If[k == n, T[s, n, k - 1], poly[s, n - k + 1] * T[s, n, k - 1] + T[s, n - 1, k]]];
    A[n_, k_] := T[n, k, k];
    Table[A[n - k, k], {n, 0, 10}, {k, 0, n}] // Flatten (* Jean-François Alcover, Nov 27 2023, from first Maple program *)
  • PARI
    A(p, n) = {
           my(CF = 1 + x,
               poly(s, n) = ((s - 2)*n^2 - (s - 4)*n)/2,
               m, P
           );
           for(k = 1, n,
               m = n - k + 1;
               P = poly(p, m);
               CF = 1/(1 - P*x*CF)
            );
            Vec(CF + O(x^(n)))
    }
    for(p = 0, 8, print(A(p, 8)))
    \\  Michel Marcus and Peter Luschny, Oct 02 2023
  • Python
    from functools import cache
    @cache
    def T(s, n, k):
        if k == 0: return 1
        if k == n: return T(s, n, k - 1)
        p = (n - k + 1) * ((s - 2) * (n - k + 1) - (s - 4)) // 2
        return p * T(s, n, k - 1) + T(s, n - 1, k)
    def A(n, k): return T(n, k, k)
    for n in range(9): print([A(n, k) for k in range(9)])
    

A192174 Triangle T(n,k) of the coefficients [x^(n-k)] of the polynomial p(0,x)=-1, p(1,x)=x and p(n,x) = x*p(n-1,x) - p(n-2,x) in row n, column k.

Original entry on oeis.org

-1, 1, 0, 1, 0, 1, 1, 0, 0, 0, 1, 0, -1, 0, -1, 1, 0, -2, 0, -1, 0, 1, 0, -3, 0, 0, 0, 1, 1, 0, -4, 0, 2, 0, 2, 0, 1, 0, -5, 0, 5, 0, 2, 0, -1, 1, 0, -6, 0, 9, 0, 0, 0, -3, 0, 1, 0, -7, 0, 14, 0, -5, 0, -5, 0, 1, 1, 0, -8, 0, 20, 0, -14, 0, -5, 0, 4, 0
Offset: 0

Views

Author

Paul Curtz, Jun 24 2011

Keywords

Comments

Consider the Catalan triangle A009766 antisymmetrically extended by a mirror along the diagonal (see also A176239):
0, -1, -1, -1, -1, -1, -1, -1,
1, 0, -1, -2, -3, -4, -5, -6,
1, 1, 0, -2, -5, -9, -14, -20,
1, 2, 2, 0, -5, -14, -28, -48,
1, 3, 5, 5, 0, -14, -42, -90,
1, 4, 9, 14, 14, 0, -42, -132,
1, 5, 14, 28, 42, 42, 0, -132,
1, 6, 20, 48, 90, 132, 132, 0.
The rows in this array are essentially the columns of T(n,k).

Examples

			Triangle begins
  -1;      # -1
   1,  0;      # x
   1,  0,  1;      # x^2+1
   1,  0,  0,  0;      # x^3
   1,  0, -1,  0, -1;      # x^4-x^2-1
   1,  0, -2,  0, -1,  0;
   1,  0, -3,  0,  0,  0,  1;
   1,  0, -4,  0,  2,  0,  2,  0;
   1,  0, -5,  0,  5,  0,  2,  0, -1;
   1,  0, -6,  0,  9,  0,  0,  0, -3,  0;
   1,  0, -7,  0, 14,  0, -5,  0, -5,  0,  1;
   1,  0, -8,  0, 20,  0,-14,  0, -5,  0,  4,  0;
   1,  0, -9,  0, 27,  0,-28,  0,  0,  0,  9,  0, -1;
		

Crossrefs

Cf. A194084. - Paul Curtz, Aug 16 2011

Programs

  • Maple
    p:= proc(n,x) option remember: if n=0 then -1 elif n=1 then x elif n>=2 then x*procname(n-1,x)-procname(n-2,x) fi: end: A192174 := proc(n,k): coeff(p(n,x),x,n-k): end: seq(seq(A192174(n,k),k=0..n), n=0..11); # Johannes W. Meijer, Aug 21 2011

Formula

Sum_{k=0..n} T(n,k) = A057079(n-1).
Apparently T(3s,2s-2) = (-1)^(s+1)*A000245(s), s >= 1.

A317302 Square array T(n,k) = (n - 2)*(k - 1)*k/2 + k, with n >= 0, k >= 0, read by antidiagonals upwards.

Original entry on oeis.org

0, 0, 1, 0, 1, 0, 0, 1, 1, -3, 0, 1, 2, 0, -8, 0, 1, 3, 3, -2, -15, 0, 1, 4, 6, 4, -5, -24, 0, 1, 5, 9, 10, 5, -9, -35, 0, 1, 6, 12, 16, 15, 6, -14, -48, 0, 1, 7, 15, 22, 25, 21, 7, -20, -63, 0, 1, 8, 18, 28, 35, 36, 28, 8, -27, -80, 0, 1, 9, 21, 34, 45, 51, 49, 36, 9, -35, -99, 0, 1, 10, 24, 40, 55, 66
Offset: 0

Views

Author

Omar E. Pol, Aug 09 2018

Keywords

Comments

Note that the formula gives several kinds of numbers, for example:
Row 0 gives 0 together with A258837.
Row 1 gives 0 together with A080956.
Row 2 gives A001477, the nonnegative numbers.
For n >= 3, row n gives the n-gonal numbers (see Crossrefs section).

Examples

			Array begins:
------------------------------------------------------------------------
n\k  Numbers       Seq. No.   0   1   2   3   4    5    6    7    8
------------------------------------------------------------------------
0    ............ (A258837):  0,  1,  0, -3, -8, -15, -24, -35, -48, ...
1    ............ (A080956):  0,  1,  1,  0, -2,  -5,  -9, -14, -20, ...
2    Nonnegatives  A001477:   0,  1,  2,  3,  4,   5,   6,   7,   8, ...
3    Triangulars   A000217:   0,  1,  3,  6, 10,  15,  21,  28,  36, ...
4    Squares       A000290:   0,  1,  4,  9, 16,  25,  36,  49,  64, ...
5    Pentagonals   A000326:   0,  1,  5, 12, 22,  35,  51,  70,  92, ...
6    Hexagonals    A000384:   0,  1,  6, 15, 28,  45,  66,  91, 120, ...
7    Heptagonals   A000566:   0,  1,  7, 18, 34,  55,  81, 112, 148, ...
8    Octagonals    A000567:   0,  1,  8, 21, 40,  65,  96, 133, 176, ...
9    9-gonals      A001106:   0,  1,  9, 24, 46,  75, 111, 154, 204, ...
10   10-gonals     A001107:   0,  1, 10, 27, 52,  85, 126, 175, 232, ...
11   11-gonals     A051682:   0,  1, 11, 30, 58,  95, 141, 196, 260, ...
12   12-gonals     A051624:   0,  1, 12, 33, 64, 105, 156, 217, 288, ...
13   13-gonals     A051865:   0,  1, 13, 36, 70, 115, 171, 238, 316, ...
14   14-gonals     A051866:   0,  1, 14, 39, 76, 125, 186, 259, 344, ...
15   15-gonals     A051867:   0,  1, 15, 42, 82, 135, 201, 280, 372, ...
...
		

Crossrefs

Column 0 gives A000004.
Column 1 gives A000012.
Column 2 gives A001477, which coincides with the row numbers.
Main diagonal gives A060354.
Row 0 gives 0 together with A258837.
Row 1 gives 0 together with A080956.
Row 2 gives A001477, the same as column 2.
For n >= 3, row n gives the n-gonal numbers: A000217 (n=3), A000290 (n=4), A000326 (n=5), A000384 (n=6), A000566 (n=7), A000567 (n=8), A001106 (n=9), A001107 (n=10), A051682 (n=11), A051624 (n=12), A051865 (n=13), A051866 (n=14), A051867 (n=15), A051868 (n=16), A051869 (n=17), A051870 (n=18), A051871 (n=19), A051872 (n=20), A051873 (n=21), A051874 (n=22), A051875 (n=23), A051876 (n=24), A255184 (n=25), A255185 (n=26), A255186 (n=27), A161935 (n=28), A255187 (n=29), A254474 (n=30).
Cf. A303301 (similar table but with generalized polygonal numbers).

Formula

T(n,k) = A139600(n-2,k) if n >= 2.
T(n,k) = A139601(n-3,k) if n >= 3.

A112466 Riordan array ((1+2*x)/(1+x), x/(1+x)).

Original entry on oeis.org

1, 1, 1, -1, 0, 1, 1, -1, -1, 1, -1, 2, 0, -2, 1, 1, -3, 2, 2, -3, 1, -1, 4, -5, 0, 5, -4, 1, 1, -5, 9, -5, -5, 9, -5, 1, -1, 6, -14, 14, 0, -14, 14, -6, 1, 1, -7, 20, -28, 14, 14, -28, 20, -7, 1, -1, 8, -27, 48, -42, 0, 42, -48, 27, -8, 1, 1, -9, 35, -75, 90, -42, -42, 90, -75, 35, -9, 1, -1, 10, -44, 110, -165, 132, 0, -132, 165, -110, 44, -10, 1
Offset: 0

Views

Author

Paul Barry, Sep 06 2005

Keywords

Comments

Inverse is A112465.
Triangle T(n,k), 0 <= k <= n, read by rows, given by [1, -2, 0, 0, 0, 0, 0, 0, 0, 0, 0, ...] DELTA [1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, ...] where DELTA is the operator defined in A084938. - Philippe Deléham, Aug 07 2006; corrected by Philippe Deléham, Dec 11 2008
Equals A097808 when the first column is removed. - Georg Fischer, Jul 26 2023

Examples

			Triangle starts
   1;
   1,  1;
  -1,  0,  1;
   1, -1, -1,  1;
  -1,  2,  0, -2,  1;
   1, -3,  2,  2, -3,  1;
  -1,  4, -5,  0,  5, -4,  1;
From _Paul Barry_, Apr 08 2011: (Start)
Production matrix begins
   1,  1;
  -2, -1,  1;
   2,  0, -1,  1;
  -2,  0,  0, -1,  1;
   2,  0,  0,  0, -1,  1;
  -2,  0,  0,  0,  0, -1,  1;
   2,  0,  0,  0,  0,  0, -1,  1; (End)
		

Crossrefs

Columns: A248157(n+2) (k=1), (-1)^n*A080956(n-2) (k=2), (-1)^(n-1)*A254749(n-2) (k=3).

Programs

  • Magma
    A112466:= func< n,k | n eq 0 select 1 else (-1)^(n+k)*(Binomial(n,k) - 2*Binomial(n-1,k)) >;
    [A112466(n,k): k in [0..n], n in [0..12]]; // G. C. Greubel, Apr 30 2025
    
  • Maple
    seq(seq( (-1)^(n-k)*(2*binomial(n-1, k-1)-binomial(n, k)), k=0..n), n=0..10); # G. C. Greubel, Feb 19 2020
  • Mathematica
    {1}~Join~Table[(Binomial[n, n - k] - 2 Binomial[n - 1, n - k - 1])*(-1)^(n - k), {n, 12}, {k, 0, n}] // Flatten (* Michael De Vlieger, Feb 18 2020 *)
  • PARI
    T(n,k) = (-1)^(n-k)*(binomial(n, n-k) - 2*binomial(n-1, n-k-1)); \\ Michel Marcus, Feb 19 2020
    
  • SageMath
    def A112466(n,k): return 1 if (n==0) else (-1)^(n+k)*(binomial(n,k) - 2*binomial(n-1,k))
    print(flatten([[A112466(n,k) for k in range(n+1)] for n in range(13)])) # G. C. Greubel, Apr 30 2025

Formula

Number triangle: T(n,k) = (-1)^(n-k)*(C(n, n-k) - 2*C(n-1, n-k-1)), with T(0,0) = 1.
T(2*n, n) = 0 (main diagonal).
Sum_{k=0..n} T(n, k) = 0 + [n=0] + 2*[n=1] (row sums).
Sum_{k=0..floor(n/2)} T(n-k, k) = (-1)^(n+1)*Fibonacci(n-2) (diagonal sums).
Sum_{k=0..n} T(n,k)*x^k = (x+1)*(x-1)^(n-1), for n >= 1. - Philippe Deléham, Oct 03 2005
T(0,0) = T(1,0) = T(1,1) = 1, T(n,k) = 0 if n < 0 or if n < k, T(n,k) = T(n-1,k-1) - T(n-1,k) for n > 1. - Philippe Deléham, Nov 26 2006
G.f.: (1+2*x)/(1+x-x*y). - R. J. Mathar, Aug 11 2015
From G. C. Greubel, Apr 30 2025: (Start)
T(2*n+1, 2*n+1-k) = T(2*n+1, k) (symmetric odd n rows).
T(2*n, 2*n-k) = (-1)*T(2*n, k) (antisymmetric even n rows).
Sum_{k=0..n} (-1)^k*T(n, k) = A000007(n) (signed row sums).
Sum_{k=0..floor(n/2)} (-1)^k*T(n-k, k) = (-1)^n*A057079(n+2) (signed diagonal sums). (End)

A176239 Shifted signed Catalan triangle T(n,k) = (-1)^*(n+k+1)*A009766(n,k-n+1) read by rows.

Original entry on oeis.org

0, -1, 1, -1, 0, 2, 0, 1, -2, 2, 0, -5, 0, 0, 1, -3, 5, -5, 0, 14, 0, 0, 0, 1, -4, 9, -14, 14, 0, -42, 0, 0, 0, 0, 1, -5, 14, -28, 42, -42, 0, 132, 0, 0, 0, 0, 0, 1, -6, 20, -48, 90, -132, 132, 0, -429, 0, 0, 0, 0, 0, 0, 1, -7, 27, -75, 165, -297, 429, -429, 0, 1430
Offset: 0

Views

Author

Paul Curtz, Apr 12 2010

Keywords

Examples

			The triangle starts in row n=0 with columns 0 <= k < 2*(n+1) as:
0,-1;                          (-1)^k*k  A001477
1,-1,.0,.2;                      (-1)^(k+1)*(k+1)*(k-2)/2  A080956, A000096
0,.1,-2,.2,.0,-5;                 (-1)^n*k*(k+1)*(k-4)/6 A129936, A005586
0,.0,.1,-3,.5,-5,..0,.14;             (-1)^k*k*(k+1)*(k-1)*(k-6)/24, A005587
0,.0,.0,.1,-4,.9,-14,.14,.0,-42;           A005557, A034807
0,.0,.0,.0,.1,-5,.14,-28,42,-42,0,132;
		

Crossrefs

Programs

  • Maple
    A009766 := proc(n,k) if k<0 or k >n then 0; else binomial(n+k,n)*(n-k+1)/(n+1) ; end if; end proc:
    A000108 := proc(n) binomial(2*n,n)/(n+1) ; end proc:
    A176239 := proc(n,k) if k <= 2*n-1 then (-1)^(n+k+1)*A009766(n,k-n+1) elif k = 2*n then 0; elif k < 2*(n+1) then (-1)^(n+1)*A000108(n+1); else 0; end if; end proc: # R. J. Mathar, Dec 03 2010

Formula

T(n,k) = T(n+1,k)+T(n+1,k+1), k <= 2n+1.
T(n,2n) = 0.
T(n,2n+1) = (-1)^(n+1)*A000108(n+1).
T(n,k) = (-1)^(n+k+1)*A009766(n,k-n+1), k < 2n.

A319933 A(n, k) = [x^k] DedekindEta(x)^n, square array read by descending antidiagonals, A(n, k) for n >= 0 and k >= 0.

Original entry on oeis.org

1, 0, 1, 0, -1, 1, 0, -1, -2, 1, 0, 0, -1, -3, 1, 0, 0, 2, 0, -4, 1, 0, 1, 1, 5, 2, -5, 1, 0, 0, 2, 0, 8, 5, -6, 1, 0, 1, -2, 0, -5, 10, 9, -7, 1, 0, 0, 0, -7, -4, -15, 10, 14, -8, 1, 0, 0, -2, 0, -10, -6, -30, 7, 20, -9, 1, 0, 0, -2, 0, 8, -5, 0, -49, 0, 27, -10, 1
Offset: 0

Views

Author

Peter Luschny, Oct 02 2018

Keywords

Comments

The columns are generated by polynomials whose coefficients constitute the triangle of signed D'Arcais numbers A078521 when multiplied with n!.

Examples

			[ 0] 1,   0,   0,    0,     0,    0,     0,     0,     0,     0, ... A000007
[ 1] 1,  -1,  -1,    0,     0,    1,     0,     1,     0,     0, ... A010815
[ 2] 1,  -2,  -1,    2,     1,    2,    -2,     0,    -2,    -2, ... A002107
[ 3] 1,  -3,   0,    5,     0,    0,    -7,     0,     0,     0, ... A010816
[ 4] 1,  -4,   2,    8,    -5,   -4,   -10,     8,     9,     0, ... A000727
[ 5] 1,  -5,   5,   10,   -15,   -6,    -5,    25,    15,   -20, ... A000728
[ 6] 1,  -6,   9,   10,   -30,    0,    11,    42,     0,   -70, ... A000729
[ 7] 1,  -7,  14,    7,   -49,   21,    35,    41,   -49,  -133, ... A000730
[ 8] 1,  -8,  20,    0,   -70,   64,    56,     0,  -125,  -160, ... A000731
[ 9] 1,  -9,  27,  -12,   -90,  135,    54,   -99,  -189,   -85, ... A010817
[10] 1, -10,  35,  -30,  -105,  238,     0,  -260,  -165,   140, ... A010818
    A001489,  v , A167541, v , A319931,  v ,         diagonal: A008705
           A080956       A319930      A319932
		

References

  • G. H. Hardy and E. M. Wright, An Introduction to the Theory of Numbers. Fifth ed., Clarendon Press, Oxford, 2003.

Crossrefs

Transpose of A286354.
Cf. A078521, A319574 (JacobiTheta3).

Programs

  • Julia
    # DedekindEta is defined in A000594
    for n in 0:10
        DedekindEta(10, n) |> println
    end
  • Maple
    DedekindEta := (x, n) -> mul(1-x^j, j=1..n):
    A319933row := proc(n, len) series(DedekindEta(x, len)^n, x, len+1):
    seq(coeff(%, x, j), j=0..len-1) end:
    seq(print([n], A319933row(n, 10)), n=0..10);
  • Mathematica
    eta[x_, n_] := Product[1 - x^j, {j, 1, n}];
    A[n_, k_] := SeriesCoefficient[eta[x, k]^n, {x, 0, k}];
    Table[A[n - k, k], {n, 0, 11}, {k, n, 0, -1}] // Flatten (* Jean-François Alcover, Nov 10 2018 *)
  • Sage
    from sage.modular.etaproducts import qexp_eta
    def A319933row(n, len):
        return (qexp_eta(ZZ['q'], len+4)^n).list()[:len]
    for n in (0..10):
        print(A319933row(n, 10))
    

A080959 Square array of coefficients of binomial polynomials, read by antidiagonals.

Original entry on oeis.org

1, 2, 1, 3, 1, 5, 4, 0, 11, 14, 5, -2, 20, 14, 94, 6, -5, 34, -10, 214, 444, 7, -9, 55, -74, 454, 444, 3828, 8, -14, 85, -200, 974, -636, 8868, 25584, 9, -20, 126, -416, 2024, -4236, 21468, 25584, 270576, 10, -27, 180, -756, 3968, -13056, 56748, -55056, 633456, 2342880, 11, -35, 249, -1260, 7308, -31632, 146208, -377616, 1722096, 2342880, 29400480
Offset: 1

Views

Author

Paul Barry, Mar 01 2003

Keywords

Examples

			Array, A(n, k), begin as:
   1,   1,   5,    14,    94,     444,    3828,      25584,     270576, ... A024167;
   2,   1,  11,    14,   214,     444,    8868,      25584,     633456, ... A080958;
   3,   0,  20,   -10,   454,    -636,   21468,     -55056,    1722096, ... ;
   4,  -2,  34,   -74,   974,   -4236,   56748,    -377616,    5471856, ... ;
   5,  -5,  55,  -200,  2024,  -13056,  146208,   -1325136,   16902576, ... ;
   6,  -9,  85,  -416,  3968,  -31632,  348816,   -3695952,   47457072, ... ;
   7, -14, 126,  -756,  7308,  -67032,  766296,   -9004752,  120758832, ... ;
   8, -20, 180, -1260, 12708, -129672, 1563336,  -19925712,  281929392, ... ;
   9, -27, 249, -1974, 21018, -234252, 2993436,  -40917312,  611923392, ... ;
  10, -35, 335, -2950, 33298, -400812, 5431116,  -79073472, 1248697152, ... ;
  11, -44, 440, -4246, 50842, -655908, 9411204, -145250688, 2417424768, ... ;
Antidiagonals, T(n, k), begin as:
   1;
   2,   1;
   3,   1,   5;
   4,   0,  11,    14;
   5,  -2,  20,    14,   94;
   6,  -5,  34,   -10,  214,    444;
   7,  -9,  55,   -74,  454,    444,   3828;
   8, -14,  85,  -200,  974,   -636,   8868,   25584;
   9, -20, 126,  -416, 2024,  -4236,  21468,   25584,  270576;
  10, -27, 180,  -756, 3968, -13056,  56748,  -55056,  633456, 2342880;
  11, -35, 249, -1260, 7308, -31632, 146208, -377616, 1722096, 2342880, 29400480;
		

Crossrefs

Columns: A000027 (k=1), A080956 (k=2), A080957 (k=3).

Programs

  • Magma
    A:= func< n,k | Factorial(k)*(&+[(-1)^(j+1)*Binomial(n+j,j)/j: j in [1..k]]) >;
    A080959:= func< n,k | A(n-k,k) >;
    [A080959(n,k): k in [1..n], n in [0..12]]; // G. C. Greubel, May 11 2025
    
  • Mathematica
    A[n_, k_]:= k!*Sum[(-1)^(j+1)*Binomial[n+j,j]/j, {j,k}];
    A080959[n_, k_]:= A[n-k, k];
    Table[A080959[n,k], {n,0,12}, {k,n}]//Flatten (* G. C. Greubel, May 11 2025 *)
  • SageMath
    def A(n,k): return factorial(k)*sum((-1)^(j+1)*binomial(n+j,j)/j for j in range(1,k+1))
    def A080959(n,k): return A(n-k,k)
    print(flatten([[A080959(n,k) for k in range(1,n+1)] for n in range(13)])) # G. C. Greubel, May 11 2025

Formula

A(n, k) = k!*Sum_{j=1..k} (-1)^(j+1)*binomial(n+j, j)/j (array).
T(n, k) = A(n-k, k) (antidiagonals).

A319930 a(n) = (1/24)*n*(n - 1)*(n - 3)*(n - 14).

Original entry on oeis.org

0, 0, 1, 0, -5, -15, -30, -49, -70, -90, -105, -110, -99, -65, 0, 105, 260, 476, 765, 1140, 1615, 2205, 2926, 3795, 4830, 6050, 7475, 9126, 11025, 13195, 15660, 18445, 21576, 25080, 28985, 33320, 38115, 43401, 49210, 55575, 62530, 70110, 78351, 87290, 96965
Offset: 0

Views

Author

Peter Luschny, Oct 02 2018

Keywords

Crossrefs

Cf. A000012 (m=0), A001489 (m=1), A080956 (m=2), A167541 (m=3), this sequence (m=4), A319931 (m=5), A319932 (m=6).
Cf. A319933.

Programs

  • Maple
    a := n -> (1/24)*n*(n-1)*(n-3)*(n-14):
    seq(a(n), n=0..44);
  • Mathematica
    Table[(n(n-1)(n-3)(n-14))/24,{n,0,70}] (* Harvey P. Dale, Apr 29 2022 *)

Formula

a(n) = [x^4] DedekindEta(x)^n.
a(n) = A319933(n, 4).

A319931 a(n) = -(1/120)*n*(n - 3)*(n - 6)*(n^2 - 21*n + 8).

Original entry on oeis.org

0, 1, 2, 0, -4, -6, 0, 21, 64, 135, 238, 374, 540, 728, 924, 1107, 1248, 1309, 1242, 988, 476, -378, -1672, -3519, -6048, -9405, -13754, -19278, -26180, -34684, -45036, -57505, -72384, -89991, -110670, -134792, -162756, -194990, -231952, -274131, -322048, -376257
Offset: 0

Views

Author

Peter Luschny, Oct 02 2018

Keywords

Crossrefs

Cf. A000012 (m=0), A001489 (m=1), A080956 (m=2), A167541 (m=3), A319930 (m=4), this sequence (m=5), A319932 (m=6).
Cf. A319933.

Programs

  • Maple
    a := n -> -(1/120)*n*(n-3)*(n-6)*(n^2-21*n+8):
    seq(a(n), n=0..41);
  • PARI
    a(n)=-n*(n-3)*(n-6)*(n^2-21*n+8)/120 \\ Charles R Greathouse IV, Oct 21 2022

Formula

a(n) = [x^5] DedekindEta(x)^n.
a(n) = A319933(n, 5).
From Chai Wah Wu, Jul 27 2022: (Start)
a(n) = 6*a(n-1) - 15*a(n-2) + 20*a(n-3) - 15*a(n-4) + 6*a(n-5) - a(n-6) for n > 5.
G.f.: x*(-7*x^4 + 6*x^3 + 3*x^2 - 4*x + 1)/(x - 1)^6. (End)

A319932 a(n) = (1/720)*n*(n - 10)*(n - 1)*(n^3 - 34*n^2 + 181*n - 144).

Original entry on oeis.org

0, 0, -2, -7, -10, -5, 11, 35, 56, 54, 0, -143, -418, -871, -1547, -2485, -3712, -5236, -7038, -9063, -11210, -13321, -15169, -16445, -16744, -15550, -12220, -5967, 4158, 19285, 40745, 70091, 109120, 159896, 224774, 306425, 407862, 532467, 684019, 866723
Offset: 0

Views

Author

Peter Luschny, Oct 02 2018

Keywords

Crossrefs

Cf. A000012 (m=0), A001489 (m=1), A080956 (m=2), A167541 (m=3), A319930 (m=4), A319931 (m=5), this sequence (m=6).
Cf. A319933.

Programs

  • Maple
    a := n -> (1/720)*n*(n-10)*(n-1)*(n^3-34*n^2+181*n-144);
    seq(a(n), n=0..39);

Formula

a(n) = [x^5] DedekindEta(x)^n.
a(n) = A319933(n, 5).
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