106280

Appears in sequences

• Number of (n+1) X (n+1) -10..10 symmetric matrices with every 2 X 2 subblock having sum zero and two distinct values.at n=18A211813
• Triangle read by rows: T(n,k) is the number of derangements in S_n with no k-cycles. 1 <= k <= n.at n=40A378495