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A207931 Number of 5Xn 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 0 0 and 1 1 1 vertically.

%I A207931 #7 Jul 22 2025 21:01:06
%S A207931 16,256,704,1936,7744,30976,111584,401956,1513992,5702544,20899776,
%T A207931 76597504,286890560,1074528400,3949990000,14520250000,54270790000,
%U A207931 202842144400,746941718600,2750522740900,10264894414720,38308375269376
%N A207931 Number of 5Xn 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 0 0 and 1 1 1 vertically.
%C A207931 Row 5 of A207928
%H A207931 R. H. Hardin, <a href="/A207931/b207931.txt">Table of n, a(n) for n = 1..210</a>
%F A207931 Empirical: a(n) = 3*a(n-2) +4*a(n-3) +219*a(n-4) +44*a(n-5) -649*a(n-6) -332*a(n-7) -11289*a(n-8) -2856*a(n-9) +35419*a(n-10) +11000*a(n-11) +223800*a(n-12) +64536*a(n-13) -768480*a(n-14) -179992*a(n-15) -1832888*a(n-16) -628056*a(n-17) +7644944*a(n-18) +1553576*a(n-19) +4884248*a(n-20) +2725688*a(n-21) -36166848*a(n-22) -7027176*a(n-23) +9071662*a(n-24) -4493576*a(n-25) +77400798*a(n-26) +15843696*a(n-27) -60481962*a(n-28) -60481962*a(n-30) -15843696*a(n-31) +77400798*a(n-32) +4493576*a(n-33) +9071662*a(n-34) +7027176*a(n-35) -36166848*a(n-36) -2725688*a(n-37) +4884248*a(n-38) -1553576*a(n-39) +7644944*a(n-40) +628056*a(n-41) -1832888*a(n-42) +179992*a(n-43) -768480*a(n-44) -64536*a(n-45) +223800*a(n-46) -11000*a(n-47) +35419*a(n-48) +2856*a(n-49) -11289*a(n-50) +332*a(n-51) -649*a(n-52) -44*a(n-53) +219*a(n-54) -4*a(n-55) +3*a(n-56) -a(n-58) for n>59
%e A207931 Some solutions for n=6
%e A207931 ..1..0..1..1..1..0....1..1..0..0..1..1....1..1..1..1..0..0....0..0..1..1..1..1
%e A207931 ..1..1..0..1..1..0....1..1..0..0..1..1....1..0..0..1..1..0....1..1..1..0..0..1
%e A207931 ..0..1..1..0..0..1....0..0..1..1..0..0....0..1..1..0..0..1....1..0..0..1..1..0
%e A207931 ..1..0..1..1..0..1....0..1..1..0..1..1....1..0..0..1..1..0....0..1..1..1..1..0
%e A207931 ..1..0..0..1..1..0....1..0..0..1..1..0....1..1..1..0..1..1....0..1..1..0..0..1
%K A207931 nonn
%O A207931 1,1
%A A207931 _R. H. Hardin_ Feb 21 2012