A110329 Diagonal sums of a number triangle related to the Pell numbers.

1, 2, 11, 76, 727, 8694, 125221, 2107448, 40577501, 879557050, 21193809151, 561950634852, 16258832340451, 509717865337646, 17211690137010377, 622780718533047664, 24039198822957409081, 985985136339748008498

Offset: 0

Author

Paul Barry, Jul 20 2005

Keywords

• easy
• nonn

Comments

Diagonal sums of A110327.

Crossrefs

Cf. A000129.

Formula

a(n)=sum{k=0..floor(n/2), (n-k)!*Pell(n-2k+1)/k!}