login
A027135
a(n) = Sum_{k=0..n} T(n,k) * T(n,2n-k), with T given by A027113.
0
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
CROSSREFS
Sequence in context: A030889 A030854 A365449 * A151134 A151135 A307816
KEYWORD
nonn
STATUS
approved