a(n) = (4*n)!/((n!)^2*(2*n)!)*Sum_{k=0..n} binomial(n,k)^2*binomial(2*k,k).
A381199
a(n) = (4*n)!/((n!)^2*(2*n)!)*Sum_{k=0..n} binomial(n,k)^2*binomial(2*k,k).
Terms
- a(0) =1a(1) =36a(2) =6300a(3) =1718640a(4) =575675100a(5) =216636756336
External references
- oeis: A381199