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.

A359200 Triangle read by rows: T(n, k) = A358125(n,k)*binomial(n-1, k), 0 <= k <= n-1.

Original entry on oeis.org

0, 1, 1, 3, 8, 3, 7, 30, 30, 7, 15, 88, 144, 88, 15, 31, 230, 520, 520, 230, 31, 63, 564, 1620, 2240, 1620, 564, 63, 127, 1330, 4620, 8120, 8120, 4620, 1330, 127, 255, 3056, 12432, 26432, 33600, 26432, 12432, 3056, 255, 511, 6894, 32112, 79968, 122976, 122976, 79968, 32112, 6894, 511
Offset: 1

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Examples

			Triangle begins:
   0;
   1,     1;
   3,     8,     3;
   7,    30,    30,      7;
  15,    88,   144,     88,     15;
  31,   230,   520,    520,    230,     31;
  63,   564,  1620,   2240,   1620,    564,     63;
 127,  1330,  4620,   8120,   8120,   4620,   1330,    127;
 255,  3056, 12432,  26432,  33600,  26432,  12432,   3056,   255;
 511,  6894, 32112,  79968, 122976, 122976,  79968,  32112,  6894,   511;
1023, 15340, 80460, 229440, 413280, 499968, 413280, 229440, 80460, 15340, 1023;
...
		

Crossrefs

Row sums give 2*A005061(n-1).

Programs

  • Maple
    T := n -> local k; seq((2^n - 2^(n - k - 1) - 2^k)*binomial(n - 1, k), k = 0 .. n - 1);
    seq(T(n), n = 1 .. 11);
  • Mathematica
    T[n_, k_] := (2^n - 2^(n - k - 1) - 2^k)*Binomial[n - 1, k]; Table[T[n, k], {n, 1, 10}, {k, 0, n - 1}] // Flatten (* Amiram Eldar, Dec 20 2022 *)

Formula

T(n, k) = (2^n - 2^(n-k-1) - 2^k)*binomial(n-1, k), for n >= 1 and 0 <= k <= n-1.