A110137 Diagonal sums of A110135 when read as a number triangle.

1, 2, 7, 22, 79, 286, 1071, 4070, 15721, 61506, 243703, 977366, 3968169, 16313842, 67942539, 286769518, 1227194947, 5326324598, 23451408843, 104753097326, 474663076539, 2181355670806, 10163422480887, 47988508807190

Offset: 0

Author

Paul Barry, Jul 13 2005

Keywords

• easy
• nonn

Formula

a(n)=sum{j=0..floor((n-2k)/2), C(n-2k, j)C(2(n-2k-j), n-2k)k^j}