a(n) = Sum_{k=0..m} T(n,k) * T(n,k+1), where m=0 for n=1; m=n+1 for n >= 2; and T is given by A026148.
A027330
a(n) = Sum_{k=0..m} T(n,k) * T(n,k+1), where m=0 for n=1; m=n+1 for n >= 2; and T is given by A026148.
Terms
- a(0) =1a(1) =6a(2) =50a(3) =394a(4) =3120a(5) =24922a(6) =200676a(7) =1627434a(8) =13282008a(9) =109014050a(10) =899304906a(11) =7452793766a(12) =62019712684a(13) =518052932358
External references
- oeis: A027330