Number of (n+2)X(2+2) 0..3 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 0 2 4 6 or 7.

A252451

Number of (n+2)X(2+2) 0..3 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 0 2 4 6 or 7.

Terms

    a(0) =228a(1) =334a(2) =959a(3) =2643a(4) =7223a(5) =20242a(6) =56643a(7) =157904a(8) =441732a(9) =1236191a(10) =3457251a(11) =9675077a(12) =27082988a(13) =75811167a(14) =212260118a(15) =594414790a(16) =1664804901a(17) =4663453223a(18) =13065449675a(19) =36610452250a(20) =102601066175a(21) =287584652400a(22) =806202954272

External references