a(n) = Sum_{k=0..n-2} T(n,k) * T(n,k+2), with T given by A026626.

A026963

a(n) = Sum_{k=0..n-2} T(n,k) * T(n,k+2), with T given by A026626.

Terms

    a(0) =1a(1) =8a(2) =52a(3) =224a(4) =987a(5) =3980a(6) =16057a(7) =63732a(8) =252424a(9) =996332a(10) =3927977a(11) =15471622a(12) =60915547a(13) =239794516a(14) =943946193a(15) =3716205884a(16) =14632901696a(17) =57631689776a(18) =227042423404a(19) =894698122022

External references