%I #5 Aug 11 2014 22:45:53

%S 5,44,377,3202,25241,179234,1147095,6679750,35730988,177168580,

%T 820755334,3576675995,14747597428,57825369396,216544923909,

%U 777378404391,2683990390975,8937664937815,28776814807337,89782546245762

%N Number of nX5 0,1 arrays indicating 2X2 subblocks of some larger (n+1)X6 binary array having determinant equal to one, with rows and columns of the latter in nondecreasing lexicographic order

%C Column 5 of A227641

%H R. H. Hardin, <a href="/A227640/b227640.txt">Table of n, a(n) for n = 1..210</a>

%H R. H. Hardin, <a href="/A227640/a227640.txt">Empirical polynomial of degree 39</a>

%F Empirical polynomial of degree 39 (see link above)

%e Some solutions for n=4

%e ..0..0..1..0..0....0..0..0..0..1....0..0..0..1..0....0..0..1..0..0

%e ..0..1..0..0..0....0..1..0..0..0....0..0..0..0..0....0..1..0..0..1

%e ..0..1..0..0..0....1..0..0..1..0....0..1..1..0..0....0..0..0..0..0

%e ..1..0..1..0..1....0..0..0..0..0....1..0..1..1..0....0..1..0..0..0

%K nonn

%O 1,1

%A _R. H. Hardin_ Jul 18 2013