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%I #4 Dec 01 2014 18:43:01
%S 618,8218,104058,1405454,18415674,246926340,3265612528,43595364706,
%T 578517868594,7707617770032,102423538312580,1363394864822130,
%U 18128275855681956,241219714389563658,3208169957082934952
%N Number of (n+1)X(5+1) 0..1 arrays with every 2X2 subblock having one or two 1s
%C Column 5 of A251326
%H R. H. Hardin, <a href="/A251323/b251323.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 10*a(n-1) +170*a(n-2) -1489*a(n-3) -8511*a(n-4) +78743*a(n-5) +147223*a(n-6) -1793473*a(n-7) -909507*a(n-8) +21389764*a(n-9) -1766361*a(n-10) -147265613*a(n-11) +55639283*a(n-12) +613951735*a(n-13) -340166865*a(n-14) -1582274681*a(n-15) +1085372756*a(n-16) +2516622952*a(n-17) -2042203758*a(n-18) -2401750473*a(n-19) +2319699490*a(n-20) +1276676483*a(n-21) -1574484075*a(n-22) -300315227*a(n-23) +622148186*a(n-24) -14501288*a(n-25) -136996062*a(n-26) +21688068*a(n-27) +15485396*a(n-28) -3992911*a(n-29) -751071*a(n-30) +287595*a(n-31) +6184*a(n-32) -7774*a(n-33) +298*a(n-34) +55*a(n-35) -2*a(n-36)
%e Some solutions for n=3
%e ..1..0..1..1..0..1....0..0..1..1..1..0....0..0..0..1..0..0....0..0..0..1..0..0
%e ..0..1..0..0..0..0....0..1..0..0..0..0....1..1..1..0..1..0....0..1..0..1..0..1
%e ..1..0..0..1..0..1....0..0..1..1..1..0....0..0..0..0..0..0....0..0..0..0..1..0
%e ..0..1..0..0..0..1....1..0..0..0..0..1....0..1..0..1..1..1....1..1..1..1..0..1
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 01 2014