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%I #4 Oct 03 2015 16:09:01
%S 318,3181,37635,420654,3896365,39348387,417279054,3999504445,
%T 39913429587,409857534030,4017392736541,40104536998707,
%U 405732145282158,4021339824862381,40178930760566115,403823141865184494
%N Number of (n+2)X(4+2) 0..1 arrays with each row divisible by 7 and column not divisible by 7, read as a binary number with top and left being the most significant bits.
%C Column 4 of A262849.
%H R. H. Hardin, <a href="/A262846/b262846.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 13*a(n-1) -30*a(n-2) +775*a(n-3) -10075*a(n-4) +23250*a(n-5) -187265*a(n-6) +2434445*a(n-7) -5617950*a(n-8) +18375455*a(n-9) -238880915*a(n-10) +551263650*a(n-11) -585288123*a(n-12) +7608745599*a(n-13) -17558643690*a(n-14) -12851058675*a(n-15) +167063762775*a(n-16) -385531760250*a(n-17) +757921180765*a(n-18) -9852975349945*a(n-19) +22737635422950*a(n-20) -1115961555955*a(n-21) +14507500227415*a(n-22) -33478846678650*a(n-23) -69403913471776*a(n-24) +902250875133088*a(n-25) -2082117404153280*a(n-26) -67517783528000*a(n-27) +877731185864000*a(n-28) -2025533505840000*a(n-29)
%e Some solutions for n=3
%e ..0..1..1..1..0..0....1..1..1..0..0..0....1..0..0..0..1..1....0..0..0..0..0..0
%e ..1..0..0..0..1..1....0..0..0..1..1..1....1..0..1..0..1..0....1..0..0..0..1..1
%e ..1..1..1..1..1..1....0..0..0..0..0..0....1..1..0..0..0..1....0..1..1..1..0..0
%e ..0..1..0..1..0..1....0..0..1..1..1..0....1..0..0..0..1..1....0..1..0..1..0..1
%e ..1..1..0..0..0..1....0..0..0..0..0..0....0..1..1..1..0..0....1..0..1..0..1..0
%Y Cf. A262849.
%K nonn
%O 1,1
%A _R. H. Hardin_, Oct 03 2015
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