259520

Appears in sequences

• a(0)=1, a(n) = n*(a(n-1)+2).at n=8A165792
• Coefficient of x in the reduction by x^2 -> x+1 of the polynomial p(n,x) defined at Comments.at n=20A192974
• Number of (n+2)X(n+2) 0..2 arrays with every 3X3 subblock having three equal elements in a row horizontally, vertically or nw-to-se diagonally exactly three ways, and new values 0..2 introduced in row major order.at n=9A204362