-9699690

Appears in sequences

• Coefficient of x^2 in 2n-th normalized Legendre polynomial.at n=9A100259
• Dirichlet inverse of A108951, primorial inflation of n.at n=18A354351
• Triangle read by rows: T(n, k) = (-1)^(n + k)*2*binomial(2*k - 1, n)* binomial(2*n + 1, 2*k) for k > 0, and k^n for k = 0.at n=53A368846