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A206997 Number of nX5 0..1 arrays avoiding 0 1 0 horizontally and 0 1 1 vertically.

%I A206997 #7 Jul 22 2025 19:54:55
%S A206997 21,441,4705,45932,382349,3032756,22816988,167677230,1207025216,
%T A206997 8591341603,60610129084,425271661995,2971839865977,20712555115779,
%U A206997 144081095381243,1000955841121092,6947328909618473,48188215073760186
%N A206997 Number of nX5 0..1 arrays avoiding 0 1 0 horizontally and 0 1 1 vertically.
%C A206997 Column 5 of A207000
%H A206997 R. H. Hardin, <a href="/A206997/b206997.txt">Table of n, a(n) for n = 1..210</a>
%F A206997 Empirical: a(n) = 18*a(n-1) -72*a(n-2) -470*a(n-3) +3911*a(n-4) +769*a(n-5) -69764*a(n-6) +99094*a(n-7) +628042*a(n-8) -1523144*a(n-9) -3140220*a(n-10) +11241633*a(n-11) +8300230*a(n-12) -50060099*a(n-13) -5933234*a(n-14) +146226346*a(n-15) -32419216*a(n-16) -293487699*a(n-17) +123234334*a(n-18) +417727459*a(n-19) -222384126*a(n-20) -431256120*a(n-21) +252100312*a(n-22) +327795585*a(n-23) -193166533*a(n-24) -184712091*a(n-25) +102596274*a(n-26) +76980256*a(n-27) -37919899*a(n-28) -23422618*a(n-29) +9646690*a(n-30) +5076967*a(n-31) -1644172*a(n-32) -754228*a(n-33) +178184*a(n-34) +72234*a(n-35) -11036*a(n-36) -3988*a(n-37) +296*a(n-38) +96*a(n-39)
%e A206997 Some solutions for n=4
%e A206997 ..1..1..0..1..1....1..1..0..1..1....1..1..0..1..1....0..0..0..1..1
%e A206997 ..1..1..1..1..1....1..0..0..0..0....0..0..0..0..0....1..0..1..1..0
%e A206997 ..0..0..0..0..0....0..1..1..0..0....1..1..1..1..1....0..0..0..0..0
%e A206997 ..0..0..1..1..1....1..0..0..1..1....0..0..0..0..0....1..1..0..0..1
%K A206997 nonn
%O A206997 1,1
%A A206997 _R. H. Hardin_ Feb 14 2012