a(n) = Sum_{k = 0..n} (-4)^(n-k)*binomial(n,k)*binomial(4*n+2*k,2*k)* binomial(2*k,k).
A363990
a(n) = Sum_{k = 0..n} (-4)^(n-k)*binomial(n,k)*binomial(4*n+2*k,2*k)* binomial(2*k,k).
Terms
- a(0) =1a(1) =26a(2) =2266a(3) =248912a(4) =30319450a(5) =3916519276a(6) =525461758576
External references
- oeis: A363990