A027241 a(n) = Sum_{k=0..n-2} T(n,k) * T(n,k+2), with T given by A026769.

1, 7, 38, 201, 991, 5119, 25108, 131207, 652171, 3467959, 17536482, 94772169, 487259131, 2668269045, 13920305080, 77008669339, 406737748473, 2267418205201, 12099265896022, 67836037484417, 365071772684071, 2055622507395167, 11141223793940397, 62938095325080771

Offset: 2

Author

Clark Kimberling

Keywords

• nonn

Extensions

More terms from Sean A. Irvine, Oct 26 2019