-120120

Appears in sequences

• Expansion of (1-4*x)^(21/2).at n=19A020933
• Triangle of coefficients of n-th degree interpolating polynomial to sqrt(x) multiplied by 4^n.at n=38A091764
• Triangle read by rows, coefficients of the Legendre polynomials P(n, x) times 2^n: T(n, k) = 2^n * [x^k] P(n, x), n >= 0, 0 <= k <= n.at n=59A157077
• Coefficient array of orthogonal polynomials whose moment sequence is the double factorial numbers A001147.at n=41A176231
• G.f.: Limit_{K->oo} Sum_{n=-oo..+oo} x^(n-K) * (1 - x^n + n*(n+1)/6 * x^(n+K))^n.at n=63A292177