a(n) = Sum_{k=0..2n-2} T(n,k) * T(n,k+2), with T given by A027023.
A027048
a(n) = Sum_{k=0..2n-2} T(n,k) * T(n,k+2), with T given by A027023.
Terms
- a(0) =5a(1) =29a(2) =213a(3) =1633a(4) =12821a(5) =102369a(6) =826305a(7) =6724933a(8) =55108961a(9) =454279229a(10) =3764205941a(11) =31334121045a(12) =261903891425
External references
- oeis: A027048