Triangle of coefficients, read by rows of (2n+1) terms, where the n-th row forms a polynomial in x, P(n,x), of degree 2n and satisfies: P(n,x) = [Sum_{k=1..n} 1/(k + x + x^2)]*[Product_{k=1..n} (k + x + x^2)].

A074248

Triangle of coefficients, read by rows of (2n+1) terms, where the n-th row forms a polynomial in x, P(n,x), of degree 2n and satisfies: P(n,x) = [Sum_{k=1..n} 1/(k + x + x^2)]*[Product_{k=1..n} (k + x + x^2)].