217683

Appears in sequences

• Number of symmetric nonnegative integer 9 X 9 matrices with sum of elements equal to 4*n, under action of dihedral group D_4.at n=10A054549
• a(n) = 6*binomial(n,4) + 6*binomial(n,3) + 4*binomial(n,2) + 2*n + 1.at n=31A385689