A131910 Central terms of triangle A131909.

1, 1, 3, 8, 26, 79, 274, 964, 3496, 12664, 46157, 168240, 615173, 2256669, 8321911, 30871862, 115280183, 433247309, 1638036186, 6225871432, 23769249188, 91077899373, 350002189936, 1348065993111, 5201249282212, 20094668668700

Offset

0,3

Links

Table of n, a(n) for n=0..25.

Formula

a(n) = A131909(2n,n) for n>=0.

Prog

(PARI)

Crossrefs

Cf. A131909.

Sequence in context: A317852 A306485 A148801 * A205775 A331320 A148802

Adjacent sequences: A131907 A131908 A131909 * A131911 A131912 A131913

Keyword

nonn

Author

Paul D. Hanna, Jul 26 2007

Status

approved