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.

A343804 T(n, k) = Sum_{j=k..n} binomial(n, j)*E2(j, j-k), where E2 are the Eulerian numbers A201637. Triangle read by rows, T(n, k) for 0 <= k <= n.

Original entry on oeis.org

1, 1, 1, 1, 4, 1, 1, 15, 11, 1, 1, 64, 96, 26, 1, 1, 325, 824, 448, 57, 1, 1, 1956, 7417, 6718, 1779, 120, 1, 1, 13699, 71595, 96633, 43411, 6429, 247, 1, 1, 109600, 746232, 1393588, 944618, 243928, 21898, 502, 1, 1, 986409, 8403000, 20600856, 19521210, 7739362, 1250774, 71742, 1013, 1
Offset: 0

Views

Author

Peter Luschny, Apr 30 2021

Keywords

Examples

			Triangle starts:
[0] 1
[1] 1, 1
[2] 1, 4,      1
[3] 1, 15,     11,      1
[4] 1, 64,     96,      26,       1
[5] 1, 325,    824,     448,      57,       1
[6] 1, 1956,   7417,    6718,     1779,     120,     1
[7] 1, 13699,  71595,   96633,    43411,    6429,    247,     1
[8] 1, 109600, 746232,  1393588,  944618,   243928,  21898,   502,   1
[9] 1, 986409, 8403000, 20600856, 19521210, 7739362, 1250774, 71742, 1013, 1
		

Crossrefs

Row sums: A084262.
Cf. A046802 (Eulerian first order).

Programs

  • Maple
    T := (n, k) -> add(binomial(n, r)*combinat:-eulerian2(r, r-k), r = k..n):
    seq(seq(T(n, k), k = 0..n), n = 0..9);