Number of (1+2)X(n+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 0 1 3 6 or 7 and every 3X3 column and antidiagonal sum not equal to 0 1 3 6 or 7.

A252306

Number of (1+2)X(n+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 0 1 3 6 or 7 and every 3X3 column and antidiagonal sum not equal to 0 1 3 6 or 7.

Terms

    a(0) =864a(1) =1126a(2) =1675a(3) =2670a(4) =4349a(5) =7138a(6) =12027a(7) =20001a(8) =33175a(9) =56339a(10) =94176a(11) =156500a(12) =266470a(13) =446079a(14) =742112a(15) =1264356a(16) =2117176a(17) =3525323a(18) =6004166a(19) =10052927a(20) =16753070a(21) =28510417a(22) =47726510a(23) =79602575a(24) =135332893a(25) =226509989a(26) =378121578a(27) =642150721

External references