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A207887 Number of 5Xn 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 1 1 and 1 1 0 vertically.

%I A207887 #7 Jul 22 2025 20:56:09
%S A207887 14,196,408,1673,4387,10207,33976,97989,250976,751786,2196861,5945255,
%T A207887 17102505,49610006,138094073,392237030,1127664930,3179722493,
%U A207887 9008231347,25741356507,72965532844,206793439533,588943622236,1672443979270
%N A207887 Number of 5Xn 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 1 1 and 1 1 0 vertically.
%C A207887 Row 5 of A207885
%H A207887 R. H. Hardin, <a href="/A207887/b207887.txt">Table of n, a(n) for n = 1..210</a>
%F A207887 Empirical: a(n) = a(n-1) +23*a(n-3) -7*a(n-4) +a(n-5) -163*a(n-6) +21*a(n-7) -a(n-8) +621*a(n-9) -133*a(n-10) -11*a(n-11) -1509*a(n-12) +415*a(n-13) +18*a(n-14) +2512*a(n-15) -453*a(n-16) -10*a(n-17) -2932*a(n-18) -81*a(n-19) -45*a(n-20) +2408*a(n-21) +527*a(n-22) +25*a(n-23) -1360*a(n-24) -362*a(n-25) -16*a(n-26) +505*a(n-27) +62*a(n-28) -a(n-29) -111*a(n-30) +10*a(n-31) +11*a(n-33) for n>35
%e A207887 Some solutions for n=4
%e A207887 ..0..0..1..0....0..1..0..0....1..0..0..1....1..0..0..1....0..0..1..1
%e A207887 ..0..1..1..1....0..1..1..0....0..0..1..1....1..1..0..0....1..0..0..1
%e A207887 ..0..0..1..0....0..1..0..0....1..0..0..1....1..0..0..1....0..0..1..1
%e A207887 ..0..1..1..1....0..1..1..1....0..1..1..1....1..1..0..0....1..0..0..1
%e A207887 ..0..0..1..0....1..1..0..0....1..0..0..1....1..0..0..1....0..0..1..1
%K A207887 nonn
%O A207887 1,1
%A A207887 _R. H. Hardin_ Feb 21 2012