A027249 a(n) = Sum_{k=0..n-2} T(n,k) * T(n,k+2), with T given by A026780.

1, 9, 59, 338, 1937, 10289, 57345, 299832, 1663421, 8705069, 48391863, 254818488, 1421911953, 7544528179, 42264280735, 225949128338, 1270219491983, 6838142459779, 38557301241769, 208865221891584, 1180647902778713, 6430734346787925, 36426544777112515, 199364753897943071

Offset

2,2

Links

Table of n, a(n) for n=2..25.

Crossrefs

Sequence in context: A308353 A280103 A174654 * A026717 A231228 A198847

Adjacent sequences: A027246 A027247 A027248 * A027250 A027251 A027252

Keyword

nonn

Author

Clark Kimberling

Extensions

More terms from Sean A. Irvine, Oct 26 2019

Status

approved