A027995 a(n) = Sum_{0<=k<=2n-1} T(n,k)*T(n,k+1), T given by A027926.

2, 9, 36, 140, 542, 2100, 8152, 31707, 123542, 482119, 1884060, 7371715, 28874778, 113213129, 444285136, 1744931000, 6858286418, 26974115244, 106157250796, 418025117820, 1646975313678, 6492134765114, 25602897974056

Offset

1,1

Links

Table of n, a(n) for n=1..23.

Crossrefs

Cf. A027926.

Sequence in context: A134759 A007946 A135593 * A077836 A003125 A055841

Adjacent sequences: A027992 A027993 A027994 * A027996 A027997 A027998

Keyword

nonn

Author

Clark Kimberling

Status

approved