Number of n X n 0..1 arrays with every element equal to 1 or 2 horizontally or antidiagonally adjacent elements, with upper left element zero.

A301818

Number of n X n 0..1 arrays with every element equal to 1 or 2 horizontally or antidiagonally adjacent elements, with upper left element zero.

Terms

    a(0) =0a(1) =2a(2) =4a(3) =68a(4) =1197a(5) =31061a(6) =2341241a(7) =221373169a(8) =47059520355

External references