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A207468 Number of 4Xn 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 1 0 and 1 0 1 vertically.

%I A207468 #7 Jul 22 2025 20:27:56
%S A207468 10,100,358,1307,4219,11760,33393,88198,229458,590832,1486909,3739145,
%T A207468 9312304,23088739,57148946,140903738,347166896,854103343,2099195971,
%U A207468 5157634036,12663610465,31086972482,76294760274,187208257122
%N A207468 Number of 4Xn 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 1 0 and 1 0 1 vertically.
%C A207468 Row 4 of A207467
%H A207468 R. H. Hardin, <a href="/A207468/b207468.txt">Table of n, a(n) for n = 1..210</a>
%F A207468 Empirical: a(n) = 2*a(n-1) +6*a(n-2) -2*a(n-3) -34*a(n-4) -4*a(n-5) +52*a(n-6) +62*a(n-7) -38*a(n-8) -7*a(n-9) -98*a(n-10) -124*a(n-11) -15*a(n-12) +265*a(n-13) +141*a(n-14) +30*a(n-15) -51*a(n-16) -198*a(n-17) -224*a(n-18) -27*a(n-19) +173*a(n-20) +99*a(n-21) +110*a(n-22) -a(n-23) -38*a(n-24) -84*a(n-25) -9*a(n-26) -17*a(n-27) +12*a(n-28) +8*a(n-29) +13*a(n-30) +2*a(n-32) -a(n-33) -a(n-34) -a(n-35)
%e A207468 Some solutions for n=4
%e A207468 ..0..0..1..0....1..1..1..1....0..1..0..0....1..1..1..1....0..0..1..0
%e A207468 ..0..0..1..0....0..1..0..1....0..1..0..1....1..1..1..1....0..0..1..0
%e A207468 ..1..0..0..1....0..1..0..0....1..0..0..1....1..1..1..1....1..1..0..0
%e A207468 ..1..1..0..1....0..1..0..0....1..0..0..1....1..0..1..0....1..1..0..0
%K A207468 nonn
%O A207468 1,1
%A A207468 _R. H. Hardin_ Feb 18 2012