A027248 a(n) = Sum_{k=0..n-1} T(n,k) * T(n,k+1), with T given by A026780.

1, 6, 29, 156, 741, 3958, 19233, 103340, 513829, 2782642, 14111035, 76987001, 396866211, 2179190558, 11387537287, 62869497136, 332264796115, 1842788400972, 9831563838105, 54737178645869, 294362713929617, 1644215891925732, 8902034364734719, 49863044050919951

Offset

1,2

Links

Table of n, a(n) for n=1..24.

Crossrefs

Sequence in context: A108982 A059724 A000708 * A192481 A020090 A020036

Adjacent sequences: A027245 A027246 A027247 * A027249 A027250 A027251

Keyword

nonn

Author

Clark Kimberling

Extensions

More terms from Sean A. Irvine, Oct 26 2019

Status

approved