Number of (2+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.
A252307
Number of (2+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) =1048a(1) =1031a(2) =1370a(3) =1992a(4) =3171a(5) =5056a(6) =7625a(7) =12412a(8) =19904a(9) =30526a(10) =49974a(11) =80432a(12) =123996a(13) =203444a(14) =327856a(15) =506772a(16) =832064a(17) =1341188a(18) =2076284a(19) =3409168a(20) =5493844a(21) =8513612a(22) =13975408a(23) =22511348a(24) =34911340a(25) =57286320a(26) =92228020a(27) =143118508a(28) =234743088
External references
- oeis: A252307