167720

Appears in sequences

• Number of line segments in regular n-gon with all diagonals drawn.at n=39A135565
• Irregular triangular array T; row n shows the coefficients of the (n-1)-st polynomial in the obverse convolution s(x)**t(x), where s(x) = n^2 x and t(x) = x+2. See Comments.at n=25A375043