A027141 a(n) = Sum_{k=0..2n-1} T(n,k) * T(n,k+1), with T given by A027113.

3, 23, 165, 1218, 9247, 71688, 564759, 4506005, 36324407, 295341956, 2418783687, 19932773439, 165151576215, 1374850036253, 11493442158373, 96443092570534, 811995039077311, 6857352935798972, 58071096513853991, 493014496906492215, 4195315394988567303

Offset

1,1

Links

Table of n, a(n) for n=1..21.

Crossrefs

Sequence in context: A037796 A331723 A212395 * A002398 A110065 A002816

Adjacent sequences: A027138 A027139 A027140 * A027142 A027143 A027144

Keyword

nonn

Author

Clark Kimberling

Extensions

More terms from Sean A. Irvine, Oct 23 2019

Status

approved