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%I #4 Jul 01 2013 20:41:18
%S 5,23,81,295,1079,3836,12954,41334,124956,359214,985377,2587934,
%T 6528298,15865511,37249628,84702904,186968944,401441143,839947739,
%U 1715449948,3424892827,6693385156,12820586861,24094606746,44476144089,80712174607
%N Number of nX4 0,1 arrays indicating 2X2 subblocks of some larger (n+1)X5 binary array having a sum of zero, with rows and columns of the latter in lexicographically nondecreasing order
%C Column 4 of A227125
%H R. H. Hardin, <a href="/A227123/b227123.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = (1/121645100408832000)*n^19 + (1/43553562624000)*n^17 + (107/8966909952000)*n^15 + (1/2905943040)*n^14 - (1275569/188305108992000)*n^13 + (23/68428800)*n^12 - (5672753/1379524608000)*n^11 + (191/6220800)*n^10 + (1099466111/1379524608000)*n^9 - (2116283/101606400)*n^8 + (12673870051501/47076277248000)*n^7 - (2627953/1555200)*n^6 + (133732420531/124540416000)*n^5 + (312421343/4276800)*n^4 - (1712634732923/2940537600)*n^3 + (154276843207/75675600)*n^2 - (88924473629/29099070)*n + 944 for n>6
%e Some solutions for n=4
%e ..1..1..1..1....1..1..1..1....0..0..0..0....0..0..0..0....1..1..0..0
%e ..1..1..0..0....1..0..0..0....0..0..0..0....0..0..0..0....1..0..0..0
%e ..1..0..0..0....1..0..0..0....0..0..0..0....0..0..0..1....0..0..0..1
%e ..0..0..0..0....0..0..0..0....0..1..0..0....0..0..0..1....0..0..1..0
%K nonn
%O 1,1
%A _R. H. Hardin_ Jul 01 2013
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