A094526 - OEIS

A094526

Square array of binomial transforms read by antidiagonals.

1, 1, 1, 1, 2, 1, 1, 3, 3, 1, 1, 4, 7, 4, 1, 1, 5, 13, 13, 5, 1, 1, 6, 21, 34, 21, 6, 1, 1, 7, 31, 73, 73, 31, 7, 1, 1, 8, 43, 136, 185, 136, 43, 8, 1, 1, 9, 57, 229, 381, 381, 229, 57, 9, 1, 1, 10, 73, 358, 685, 826, 685, 358, 73, 10, 1, 1, 11, 91, 529, 1121, 1531

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OFFSET

0,5

COMMENTS

Rows (and columns) are binomial transforms of [1,k,k(k-1),k(k-1)(k-2),0,0,...], k>=0. One of a family of arrays that converge to A088699.

LINKS

Table of n, a(n) for n=0..71.

FORMULA

Square array T(n, k) defined by T(n, k)=1+kn+k(k-1)n(n-1)/2+k(k-1)(k-2)n(n-1)(n-2)/6

EXAMPLE

Rows start

1,1,1,1,1,...