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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.

A368759 Square array T(n,k), n >= 0, k >= 0, read by antidiagonals downwards, where T(n,k) = n! * (1 + Sum_{j=0..n} j^k/j!).

Original entry on oeis.org

2, 1, 3, 1, 2, 7, 1, 2, 6, 22, 1, 2, 8, 21, 89, 1, 2, 12, 33, 88, 446, 1, 2, 20, 63, 148, 445, 2677, 1, 2, 36, 141, 316, 765, 2676, 18740, 1, 2, 68, 351, 820, 1705, 4626, 18739, 149921, 1, 2, 132, 933, 2428, 4725, 10446, 32431, 149920, 1349290, 1, 2, 260, 2583, 7828, 15265, 29646, 73465, 259512, 1349289, 13492901
Offset: 0

Views

Author

Seiichi Manyama, Jan 04 2024

Keywords

Examples

			Square array begins:
     2,    1,    1,     1,     1,     1,      1, ...
     3,    2,    2,     2,     2,     2,      2, ...
     7,    6,    8,    12,    20,    36,     68, ...
    22,   21,   33,    63,   141,   351,    933, ...
    89,   88,  148,   316,   820,  2428,   7828, ...
   446,  445,  765,  1705,  4725, 15265,  54765, ...
  2677, 2676, 4626, 10446, 29646, 99366, 375246, ...
		

Crossrefs

Columns k=0..3 give A038159, A033540(n+1), A053817, A368760.
Cf. A337085.

Programs

  • PARI
    T(n, k) = n!*(1+sum(j=0, n, j^k/j!));

Formula

T(0,k) = 1 + 0^k and T(n,k) = n^k + n * T(n-1,k) for n>0.
T(n,k) = n! + A337085(n,k).
E.g.f. of column k: (1+ B_k(x) * exp(x)) / (1-x), where B_n(x) = Bell polynomials.