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A207690 Number of nX5 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 0 1 and 1 1 1 vertically.

%I A207690 #7 Jul 22 2025 20:40:43
%S A207690 15,225,240,768,1872,4216,10000,24420,59616,138724,336400,811240,
%T A207690 1923276,4654480,11091620,26621504,64022280,152678176,367544432,
%U A207690 879654400,2106871848,5061876412,12106779344,29061344972,69658807392,166845800312
%N A207690 Number of nX5 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 0 1 and 1 1 1 vertically.
%C A207690 Column 5 of A207693
%H A207690 R. H. Hardin, <a href="/A207690/b207690.txt">Table of n, a(n) for n = 1..210</a>
%F A207690 Empirical: a(n) = a(n-2) +12*a(n-3) +2*a(n-4) +12*a(n-5) -56*a(n-6) +12*a(n-7) -42*a(n-8) +143*a(n-9) -13*a(n-10) +33*a(n-11) -192*a(n-12) -6*a(n-13) +43*a(n-14) +175*a(n-15) +11*a(n-16) -57*a(n-17) -102*a(n-18) +5*a(n-19) +10*a(n-20) +39*a(n-21) +2*a(n-23) -9*a(n-24) +a(n-27) for n>29
%e A207690 Some solutions for n=4
%e A207690 ..0..1..1..0..1....1..1..0..1..1....0..1..1..1..0....1..1..0..0..1
%e A207690 ..1..1..0..1..1....0..1..1..0..0....1..1..0..0..1....1..0..1..1..0
%e A207690 ..0..0..1..1..0....1..0..0..1..1....1..0..1..1..1....0..1..1..1..1
%e A207690 ..1..1..1..0..1....0..1..1..0..1....0..1..1..1..0....1..1..0..0..1
%K A207690 nonn
%O A207690 1,1
%A A207690 _R. H. Hardin_ Feb 19 2012