a(n) = Sum_{k=0..n} 2^(n-k) * binomial(4*n+2,k) * binomial(4*n-k-1,n-k).
A386867
a(n) = Sum_{k=0..n} 2^(n-k) * binomial(4*n+2,k) * binomial(4*n-k-1,n-k).
Terms
- a(0) =1a(1) =12a(2) =249a(3) =5842a(4) =144636a(5) =3690840a(6) =96028606a(7) =2532467934a(8) =67454242092
External references
- oeis: A386867