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%I #4 Jul 25 2013 21:24:52
%S 13,129,1122,10092,90881,817897,7363367,66282981,596664236,5371092567,
%T 48349664362,435235707529,3917920494766,35268475932174,
%U 317481024485129,2857912000299502,25726454110486757,231585311593846637
%N Number of nX4 0,1 arrays indicating 2X2 subblocks of some larger (n+1)X5 binary array having determinant equal to one
%C Column 4 of A227751
%H R. H. Hardin, <a href="/A227749/b227749.txt">Table of n, a(n) for n = 1..133</a>
%F Empirical: a(n) = a(n-1) +33*a(n-2) +232*a(n-3) +812*a(n-4) +1991*a(n-5) +3005*a(n-6) +2962*a(n-7) +599*a(n-8) -1449*a(n-9) +1224*a(n-10) +6483*a(n-11) +7495*a(n-12) -8986*a(n-13) -25763*a(n-14) -15443*a(n-15) +19185*a(n-16) +23662*a(n-17) -10225*a(n-18) -2280*a(n-19) +2949*a(n-20) -771*a(n-21) +4406*a(n-22) -3917*a(n-23) -2257*a(n-24) +483*a(n-25) +1552*a(n-26) -349*a(n-27) -456*a(n-28) +127*a(n-29) +91*a(n-30) -32*a(n-31) +4*a(n-32)
%e Some solutions for n=4
%e ..1..1..0..0....0..1..0..0....1..0..1..1....0..1..1..0....0..0..0..0
%e ..0..0..0..1....0..1..0..1....0..1..0..0....0..0..0..0....0..1..1..0
%e ..1..0..0..0....0..0..0..1....0..1..0..1....1..0..0..0....0..0..1..1
%e ..0..1..0..1....1..0..0..0....1..0..0..0....1..0..1..1....0..0..0..0
%K nonn
%O 1,1
%A _R. H. Hardin_ Jul 25 2013
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