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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.

A354796 Triangle read by rows. T(n, k) = Gamma(k + n) / k! for n >= 1 and 0 <= k <= n, T(0, 0) = 1.

Original entry on oeis.org

1, 1, 1, 1, 2, 3, 2, 6, 12, 20, 6, 24, 60, 120, 210, 24, 120, 360, 840, 1680, 3024, 120, 720, 2520, 6720, 15120, 30240, 55440, 720, 5040, 20160, 60480, 151200, 332640, 665280, 1235520, 5040, 40320, 181440, 604800, 1663200, 3991680, 8648640, 17297280, 32432400
Offset: 0

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Author

Peter Luschny, Jun 11 2022

Keywords

Examples

			Table T(n, k) begins:
[0]   1;
[1]   1,    1;
[2]   1,    2,     3;
[3]   2,    6,    12,    20;
[4]   6,   24,    60,   120,    210;
[5]  24,  120,   360,   840,   1680,   3024;
[6] 120,  720,  2520,  6720,  15120,  30240,  55440;
[7] 720, 5040, 20160, 60480, 151200, 332640, 665280, 1235520;
		

Crossrefs

Cf. A006963 (main diagonal),

Programs

  • Maple
    T := (n, k) -> ifelse(n = 0, 1, GAMMA(k + n) / GAMMA(k + 1));
    for n from 0 to 9 do seq(T(n, k), k = 0..n) od;
  • Mathematica
    T[0, 0] = 1; T[n_, k_] := Gamma[n + k]/Gamma[k + 1]; Table[T[n, k], {n, 0, 8}, {k, 0, n}] // Flatten (* Amiram Eldar, Jun 11 2022 *)

Formula

T(n, k) = binomial(n + k - 1, n - 1)*(n - 1)! for n >= 1.
T(n, n) = Sum_{k=0..n-1} T(n, k). Row sums are 2*A006963(n + 1) for n >= 1.