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

A252642

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

Terms

    a(0) =687a(1) =1684a(2) =4026a(3) =8253a(4) =22701a(5) =56953a(6) =121016a(7) =345360a(8) =878052a(9) =1896105a(10) =5611265a(11) =14356645a(12) =31417221a(13) =96208961a(14) =247141229a(15) =546972786a(16) =1726721164a(17) =4448939128a(18) =9937685585a(19) =32176231897a(20) =83097996347a(21) =186944826455a(22) =617389289663

External references