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

A252026

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

Terms

    a(0) =227a(1) =323a(2) =781a(3) =1929a(4) =5285a(5) =14831a(6) =41745a(7) =117867a(8) =332997a(9) =941237a(10) =2660915a(11) =7523177a(12) =21271317a(13) =60144341a(14) =170058799a(15) =480846469a(16) =1359611219a(17) =3844354431a(18) =10870074659a(19) =30735606793a(20) =86906264441a(21) =245731273709a(22) =694815999081

External references