a(n) = Sum_{k=0..m-2} T(n,k) * T(n,k+2), where m=n for n=0,1,2,3; m=2n for n >= 4; and T is given by A026082.
A027317
a(n) = Sum_{k=0..m-2} T(n,k) * T(n,k+2), where m=n for n=0,1,2,3; m=2n for n >= 4; and T is given by A026082.
Terms
- a(0) =1a(1) =6a(2) =71a(3) =561a(4) =4797a(5) =41462a(6) =359530a(7) =3124752a(8) =27213084a(9) =237432807a(10) =2075064759a(11) =18162872365a(12) =159198909233
External references
- oeis: A027317