A107704 Diagonal sums of A103209, viewed as number triangle.

1, 1, 2, 3, 8, 26, 107, 492, 2481, 13599, 81288, 531343, 3790344, 29279668, 242278645, 2125160800, 19608039385, 189437263949, 1912477987102, 20161911603747, 221869317899264, 2546362514225134, 30430660439311103

Offset

0,3

Links

Table of n, a(n) for n=0..22.

Formula

a(n)=sum{k=0..floor(n/2), sum{j=0..n-2k, C(n-2k+j, 2j)*k^j*C(k)}}, C(n) given by A000108.

Crossrefs

Sequence in context: A111121 A358280 A343438 * A246446 A296093 A041399

Adjacent sequences: A107701 A107702 A107703 * A107705 A107706 A107707

Keyword

easy,nonn

Author

Paul Barry, May 21 2005

Status

approved