Number of (n+2)X(1+2) 0..4 arrays with every consecutive three elements in every row and column not having exactly two distinct values, and in every diagonal and antidiagonal having exactly two distinct values, and new values 0 upwards introduced in row major order.

A252804

Number of (n+2)X(1+2) 0..4 arrays with every consecutive three elements in every row and column not having exactly two distinct values, and in every diagonal and antidiagonal having exactly two distinct values, and new values 0 upwards introduced in row major order.

Terms

    a(0) =61a(1) =155a(2) =357a(3) =752a(4) =1808a(5) =4045a(6) =8513a(7) =19432a(8) =42308a(9) =88615a(10) =195983a(11) =419484a(12) =874694a(13) =1895805a(14) =4011411a(15) =8333938a(16) =17813212a(17) =37386641a(18) =77434349a(19) =163852856a(20) =341828544a(21) =706141671a(22) =1482930443a(23) =3079373684a(24) =6347000002a(25) =13250880877a(26) =27415373151

External references