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A206880 Number of nX5 0..1 arrays avoiding 0 1 0 horizontally and 1 0 1 vertically.

%I A206880 #7 Jul 22 2025 19:46:04
%S A206880 21,441,4705,44879,472412,5179587,56006452,599130203,6415489317,
%T A206880 68862978274,739329103913,7933883243105,85128813219141,
%U A206880 913482746325836,9802626037683613,105191549603928895,1128793872954895887
%N A206880 Number of nX5 0..1 arrays avoiding 0 1 0 horizontally and 1 0 1 vertically.
%C A206880 Column 5 of A206883
%H A206880 R. H. Hardin, <a href="/A206880/b206880.txt">Table of n, a(n) for n = 1..210</a>
%F A206880 Empirical: a(n) = 13*a(n-1) -58*a(n-2) +347*a(n-3) +140*a(n-4) -530*a(n-5) +9303*a(n-6) -13514*a(n-7) -121746*a(n-8) -15323*a(n-9) +33707*a(n-10) +628740*a(n-11) +4819689*a(n-12) +602012*a(n-13) -24971113*a(n-14) -13357992*a(n-15) +40761516*a(n-16) +18020830*a(n-17) +237812*a(n-18) +65671414*a(n-19) -52609938*a(n-20) -104608842*a(n-21) -22319213*a(n-22) -34182852*a(n-23) +6860648*a(n-24) +108480290*a(n-25) +10214575*a(n-26) +135798774*a(n-27) -108129644*a(n-28) +67839752*a(n-29) -80003650*a(n-30) -10669415*a(n-31) +2001098*a(n-32) -14730061*a(n-33) +19683840*a(n-34) -5357218*a(n-35) +7501826*a(n-36) +833478*a(n-37) -2016577*a(n-38) +1994060*a(n-39) -1415538*a(n-40) +322598*a(n-41) +24377*a(n-42) -86458*a(n-43) +24377*a(n-44) +2403*a(n-45) -802*a(n-46) +255*a(n-47) -a(n-48) +20*a(n-49) -5*a(n-50) +a(n-51)
%e A206880 Some solutions for n=4
%e A206880 ..1..1..0..1..1....0..1..1..1..0....1..0..1..1..0....1..0..1..1..0
%e A206880 ..1..0..0..1..1....1..1..0..1..1....0..0..0..1..1....1..0..0..0..1
%e A206880 ..0..0..1..1..1....1..0..0..1..1....0..0..0..1..1....0..0..0..0..0
%e A206880 ..0..0..0..1..1....0..0..0..0..0....1..0..1..1..0....0..1..1..0..0
%K A206880 nonn
%O A206880 1,1
%A A206880 _R. H. Hardin_ Feb 13 2012