250543370

Appears in sequences

• a(n) = binomial(5*n, n)/(4*n + 1).at n=10A002294
• a(4n+k) = (k+1)*binomial(5n+k,n)/(4n+k+1), k=0..3.at n=40A118968
• G.f. A(x) satisfies A(x) = 1 + x*A(x)^3*A(-x)^2.at n=20A143546