317678760

Appears in sequences

• Square array read by ascending antidiagonals: T(n,k) = [x^k] (1 - x)^(2*k) * Legendre_P(n*k-1, (1 + x)/(1 - x)) for n, k >= 0.at n=50A364513
• a(n) = (1/2) * (6*n)!*(2*n)!^2/((3*n)!*(4*n)!*n!^3) for n >= 1 with a(0) = 1.at n=5A364515