# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a252028 Showing 1-1 of 1 %I A252028 #4 Dec 12 2014 17:14:17 %S A252028 809,1929,7182,29781,126920,541544,2306234,9836361,42007667,179412369, %T A252028 766247783,3273106717,13982899118,59736693957,255202401835, %U A252028 1090262794558,4657798693225,19899000968428,85012294225985,363188622741325 %N A252028 Number of (n+2)X(4+2) 0..2 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 0 2 or 4 %C A252028 Column 4 of A252032 %H A252028 R. H. Hardin, Table of n, a(n) for n = 1..210 %F A252028 Empirical: a(n) = 5*a(n-1) -4*a(n-2) +14*a(n-3) -23*a(n-4) -91*a(n-5) -13*a(n-6) -118*a(n-7) +815*a(n-8) +1080*a(n-9) -692*a(n-10) -2103*a(n-11) -5420*a(n-12) +2379*a(n-13) +8473*a(n-14) +4179*a(n-15) +8147*a(n-16) -18588*a(n-17) -30186*a(n-18) +2771*a(n-19) +28308*a(n-20) +32734*a(n-21) +6559*a(n-22) -23299*a(n-23) -16727*a(n-24) -666*a(n-25) +7553*a(n-26) -5973*a(n-27) -14481*a(n-28) +7873*a(n-29) +34754*a(n-30) +25934*a(n-31) -15978*a(n-32) -45920*a(n-33) -43974*a(n-34) -14735*a(n-35) +6402*a(n-36) +15091*a(n-37) +14803*a(n-38) +11460*a(n-39) +9120*a(n-40) +5581*a(n-41) +3303*a(n-42) +1366*a(n-43) +342*a(n-44) +18*a(n-45) -72*a(n-46) for n>50 %e A252028 Some solutions for n=4 %e A252028 ..1..0..2..1..2..2....2..1..2..2..2..2....1..2..2..2..1..2....2..1..2..2..2..1 %e A252028 ..0..2..1..2..2..1....2..2..2..2..2..1....2..2..2..2..2..1....1..2..2..2..2..2 %e A252028 ..2..1..2..2..1..2....2..2..2..2..2..2....2..2..2..2..2..2....2..2..2..2..1..2 %e A252028 ..1..2..2..1..2..2....2..2..2..2..2..2....1..2..2..2..2..2....2..2..2..2..2..2 %e A252028 ..2..2..1..2..2..1....1..2..2..2..2..2....2..1..2..2..1..2....2..1..2..2..2..2 %e A252028 ..2..1..2..2..1..0....2..2..1..2..2..2....0..2..1..2..2..2....2..2..2..1..2..2 %K A252028 nonn %O A252028 1,1 %A A252028 _R. H. Hardin_, Dec 12 2014 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE