A027135 a(n) = Sum_{k=0..n} T(n,k) * T(n,2n-k), with T given by A027113.

1, 3, 11, 46, 180, 707, 2729, 10377, 39045, 145493, 537749, 1973915, 7202499, 26144901, 94475783, 340028026, 1219451204, 4359473611, 15540448583, 55255188413, 196004642045, 693798921723, 2451058691129, 8643625483966

Offset

0,2

Links

Table of n, a(n) for n=0..23.

Crossrefs

Sequence in context: A030889 A030854 A365449 * A151134 A151135 A307816

Adjacent sequences: A027132 A027133 A027134 * A027136 A027137 A027138

Keyword

nonn

Author

Clark Kimberling

Status

approved