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.

A382629 Triangle T(n,k), n >= 0, 0 <= k <= n, read by rows, where T(n,k) = (n-k)*T(n-1,k-1) + 2*(k+1)*T(n-1,k) + A102365(n,k) with T(n,k) = 0 if k < 0 or k > n.

Original entry on oeis.org

1, 3, 0, 7, 4, 0, 15, 35, 5, 0, 31, 203, 115, 6, 0, 63, 994, 1428, 315, 7, 0, 127, 4470, 13421, 7450, 783, 8, 0, 255, 19185, 108156, 121314, 32865, 1839, 9, 0, 511, 80161, 793704, 1593902, 870191, 130665, 4171, 10, 0, 1023, 329648, 5483093, 18269658, 17591035, 5383906, 485166, 9251, 11, 0
Offset: 0

Views

Author

Seiichi Manyama, Apr 01 2025

Keywords

Examples

			Triangle begins:
    1;
    3,     0;
    7,     4,      0;
   15,    35,      5,       0;
   31,   203,    115,       6,      0;
   63,   994,   1428,     315,      7,      0;
  127,  4470,  13421,    7450,    783,      8,    0;
  255, 19185, 108156,  121314,  32865,   1839,    9,  0;
  511, 80161, 793704, 1593902, 870191, 130665, 4171, 10, 0;
  ...
		

Crossrefs

Row sums give A180875.
Column k=0 gives A126646.

Programs

  • PARI
    a102365(n, k) = if(k==0, 1, if(nn, 0, (n-k)*T(n-1, k-1)+2*(k+1)*T(n-1, k)+a102365(n, k));

Formula

(2/3)^n * Sum_{k=0..n} T(n,k)/2^k = A098830(n).