A109245 Diagonal sums of number triangle A109244.

1, 1, 5, 15, 54, 193, 708, 2627, 9846, 37178, 141223, 539047, 2065813, 7943706, 30634329, 118433821, 458867295, 1781267606, 6926405025, 26973935420, 105189301334, 410707352869, 1605379739149, 6281519778025, 24601184635436

Offset: 0

Author

Paul Barry, Jun 23 2005

Keywords

• easy
• nonn

Formula

G.f.: 1/((1-xc(x)-2x^2c(x)^2)(1-x^2c(x))), c(x) the g.f. of A000108.