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A207905 Number of nX5 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 0 0 and 0 1 1 vertically.

%I A207905 #7 Jul 22 2025 20:58:04
%S A207905 15,225,1071,4089,13865,39831,110775,289467,730377,1811997,4393069,
%T A207905 10558951,25146429,59475625,140190519,329138641,771108603,1803405621,
%U A207905 4211351857,9825749755,22905455175,53364801587,124272402673,289284276825
%N A207905 Number of nX5 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 0 0 and 0 1 1 vertically.
%C A207905 Column 5 of A207908
%H A207905 R. H. Hardin, <a href="/A207905/b207905.txt">Table of n, a(n) for n = 1..210</a>
%F A207905 Empirical: a(n) = 6*a(n-1) -8*a(n-2) -10*a(n-3) +3*a(n-4) +80*a(n-5) -71*a(n-6) -74*a(n-7) -24*a(n-8) +242*a(n-9) -136*a(n-10) +56*a(n-11) -102*a(n-12) +102*a(n-13) -348*a(n-14) +344*a(n-15) -2*a(n-16) +120*a(n-17) -298*a(n-18) +222*a(n-19) -192*a(n-20) +82*a(n-21) -56*a(n-22) +142*a(n-23) -104*a(n-24) +48*a(n-25) -26*a(n-26) +18*a(n-27) -27*a(n-28) +18*a(n-29) -6*a(n-30) +2*a(n-31) -a(n-32) +2*a(n-33) -a(n-34)
%e A207905 Some solutions for n=4
%e A207905 ..0..1..1..1..0....0..0..1..1..0....1..1..1..1..1....1..0..1..1..0
%e A207905 ..1..1..1..0..1....1..1..1..1..1....1..1..1..1..0....0..1..1..1..0
%e A207905 ..0..1..1..0..0....0..0..1..1..0....0..0..1..1..0....1..0..0..1..1
%e A207905 ..0..0..1..1..1....1..0..1..1..1....0..0..1..1..1....0..0..1..1..0
%K A207905 nonn
%O A207905 1,1
%A A207905 _R. H. Hardin_ Feb 21 2012