1/25 the number of (n+1)X5 0..4 arrays with every 2X2 subblock having equal diagonal elements or equal antidiagonal elements.

A203652

1/25 the number of (n+1)X5 0..4 arrays with every 2X2 subblock having equal diagonal elements or equal antidiagonal elements.

Terms

    a(0) =6561a(1) =519445a(2) =44577561a(3) =3906948333a(4) =343812029649

External references