a(n) = Sum_{k=0..2n-2} T(n,k) * T(n,k+2), with T given by A027113.
A027142
a(n) = Sum_{k=0..2n-2} T(n,k) * T(n,k+2), with T given by A027113.
Terms
- a(0) =12a(1) =105a(2) =831a(3) =6648a(4) =53545a(5) =434458a(6) =3548871a(7) =29166324a(8) =241006333a(9) =2001145585a(10) =16688238416a(11) =139711675493
External references
- oeis: A027142