212537

Appears in sequences

• Number of n X n 0..1 arrays with each 1 adjacent to 0, 1 or 3 king-move neighboring 1's.at n=4A296644
• Number of nX5 0..1 arrays with each 1 adjacent to 0, 1 or 3 king-move neighboring 1s.at n=4A296648
• T(n,k)=Number of nXk 0..1 arrays with each 1 adjacent to 0, 1 or 3 king-move neighboring 1s.at n=40A296651
• a(n) = Sum_{1 <= i, j, k, l <= n} gcd(i,j,k,l).at n=20A344523