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A207561 Number of nX5 0..1 arrays avoiding 0 0 1 and 0 1 0 horizontally and 0 1 1 and 1 1 0 vertically.

%I A207561 #7 Jul 22 2025 20:35:03
%S A207561 14,196,720,2234,9568,36426,160652,666212,2958300,12763810,56890052,
%T A207561 250429286,1120029716,4985081444,22367733696,100216967838,
%U A207561 450974257968,2029310442178,9154744404876,41320179008364,186800175680348
%N A207561 Number of nX5 0..1 arrays avoiding 0 0 1 and 0 1 0 horizontally and 0 1 1 and 1 1 0 vertically.
%C A207561 Column 5 of A207564
%H A207561 R. H. Hardin, <a href="/A207561/b207561.txt">Table of n, a(n) for n = 1..210</a>
%F A207561 Empirical: a(n) = 12*a(n-1) -18*a(n-2) -286*a(n-3) +990*a(n-4) +2420*a(n-5) -13219*a(n-6) -7318*a(n-7) +87016*a(n-8) -13474*a(n-9) -326656*a(n-10) +164320*a(n-11) +729389*a(n-12) -512204*a(n-13) -962042*a(n-14) +804466*a(n-15) +713562*a(n-16) -680852*a(n-17) -265049*a(n-18) +296838*a(n-19) +35044*a(n-20) -56802*a(n-21) +984*a(n-22) +2880*a(n-23) for n>24
%e A207561 Some solutions for n=4
%e A207561 ..1..1..1..1..0....1..0..0..0..0....1..0..1..1..1....1..0..1..1..1
%e A207561 ..1..1..1..1..1....0..1..1..1..1....1..0..1..1..0....1..1..0..0..0
%e A207561 ..1..1..1..1..0....0..0..0..0..0....1..1..1..1..1....1..0..1..1..0
%e A207561 ..1..1..1..1..1....0..1..1..1..1....1..0..1..1..0....1..1..0..0..0
%K A207561 nonn
%O A207561 1,1
%A A207561 _R. H. Hardin_ Feb 18 2012