A024721 a(n) = (1/5)*(4 + sum of C(5k,k)) for k = 0,1,2,...,n.

1, 2, 11, 102, 1071, 11697, 130452, 1475356, 16856293, 194088920, 2248544554, 26179257724, 306051026719, 3590265729775, 42241017111607, 498243554454823, 5889887780556528, 69761293355975193, 827690921897694948

Offset

0,2

Links

Harvey P. Dale, Table of n, a(n) for n = 0..922

Mathematica

(Accumulate[Table[Binomial[5n, n], {n, 0, 20}]]+4)/5 (* Harvey P. Dale, Jul 27 2021 *)

Crossrefs

Sequence in context: A130150 A115941 A351622 * A367852 A285199 A339081

Adjacent sequences: A024718 A024719 A024720 * A024722 A024723 A024724

Keyword

nonn

Author

Clark Kimberling

Extensions

More terms from James A. Sellers, May 01 2000

Status

approved