A027280 a(n) = Sum_{k=0..2n-3} T(n,k) * T(n,k+3), with T given by A026568.

26, 164, 1224, 7664, 51488, 326456, 2126376, 13574046, 87554326, 560845908, 3607790136, 23158545126, 148945375022, 957564479960, 6162874994108, 39672627184498, 255578754020002, 1647166273816172, 10622076015026288, 68529892093271816, 442357250742603624

Offset

3,1

Links

Table of n, a(n) for n=3..23.

Crossrefs

Sequence in context: A042314 A280213 A200874 * A006354 A249292 A279744

Adjacent sequences: A027277 A027278 A027279 * A027281 A027282 A027283

Keyword

nonn

Author

Clark Kimberling

Extensions

More terms from Sean A. Irvine, Oct 26 2019

Status

approved