301262

Appears in sequences

• Number of symmetric {-1, +1} matrices of order n with nonnegative row and column sums.at n=5A027832
• Number of n X n symmetric binary matrices with no row sum greater than 3.at n=6A139679
• Array read by antidiagonals: T(n,k) is the number of n X n symmetric binary matrices with no row sum greater than k.at n=51A334548