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A207348 Number of 4Xn 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 0 0 and 1 1 1 vertically.

%I A207348 #7 Jul 22 2025 20:18:59
%S A207348 10,100,292,828,2190,5290,12292,27978,62574,136978,298386,642668,
%T A207348 1375596,2932342,6217164,13153676,27743768,58404696,122773834,
%U A207348 257696786,540439948,1132381262,2371176338,4962720854,10382009670,21712572508
%N A207348 Number of 4Xn 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 0 0 and 1 1 1 vertically.
%C A207348 Row 4 of A207346
%H A207348 R. H. Hardin, <a href="/A207348/b207348.txt">Table of n, a(n) for n = 1..210</a>
%F A207348 Empirical: a(n) = 2*a(n-1) +3*a(n-2) +a(n-3) -16*a(n-4) -5*a(n-5) -2*a(n-6) +38*a(n-7) +8*a(n-8) +26*a(n-9) -59*a(n-10) +12*a(n-11) -61*a(n-12) +55*a(n-13) -57*a(n-14) +59*a(n-15) -62*a(n-16) +61*a(n-17) -41*a(n-18) +48*a(n-19) -31*a(n-20) +19*a(n-21) -20*a(n-22) +7*a(n-23) -5*a(n-24) +4*a(n-25) +a(n-27) for n>28
%e A207348 Some solutions for n=4
%e A207348 ..0..0..1..0....1..0..0..1....1..1..1..0....0..1..0..0....0..0..1..0
%e A207348 ..0..1..0..0....0..1..0..0....0..1..0..1....0..0..1..0....0..0..1..0
%e A207348 ..1..1..0..1....1..1..1..1....0..0..1..0....1..0..0..1....1..1..0..1
%e A207348 ..1..0..1..0....0..0..1..0....1..1..1..1....0..1..0..0....1..1..0..0
%K A207348 nonn
%O A207348 1,1
%A A207348 _R. H. Hardin_ Feb 17 2012