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A207513 Number of nX7 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 0 1 and 1 1 1 vertically.

%I A207513 #7 Jul 22 2025 20:31:43
%S A207513 25,625,1292,4168,11465,22960,50322,105370,214519,434467,859485,
%T A207513 1700263,3341334,6498994,12653384,24514485,47342410,91409818,
%U A207513 176001232,338633421,651272262,1250858298,2403095620,4614434368,8859453967,17015312734
%N A207513 Number of nX7 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 0 1 and 1 1 1 vertically.
%C A207513 Column 7 of A207514
%H A207513 R. H. Hardin, <a href="/A207513/b207513.txt">Table of n, a(n) for n = 1..210</a>
%F A207513 Empirical: a(n) = -4*a(n-1) +2*a(n-2) +44*a(n-3) +83*a(n-4) -88*a(n-5) -571*a(n-6) -668*a(n-7) +885*a(n-8) +3568*a(n-9) +3263*a(n-10) -3896*a(n-11) -13406*a(n-12) -11680*a(n-13) +9170*a(n-14) +33932*a(n-15) +30965*a(n-16) -12176*a(n-17) -61050*a(n-18) -59008*a(n-19) +8300*a(n-20) +81696*a(n-21) +81692*a(n-22) -1856*a(n-23) -88125*a(n-24) -86964*a(n-25) +1429*a(n-26) +84536*a(n-27) +77400*a(n-28) -5856*a(n-29) -74000*a(n-30) -60856*a(n-31) +8163*a(n-32) +56232*a(n-33) +41701*a(n-34) -7180*a(n-35) -36018*a(n-36) -24376*a(n-37) +5074*a(n-38) +19908*a(n-39) +12383*a(n-40) -3116*a(n-41) -9871*a(n-42) -5676*a(n-43) +1555*a(n-44) +4404*a(n-45) +2421*a(n-46) -464*a(n-47) -1595*a(n-48) -860*a(n-49) +38*a(n-50) +428*a(n-51) +215*a(n-52) +4*a(n-53) -102*a(n-54) -44*a(n-55) -3*a(n-56) +16*a(n-57) +4*a(n-58) -a(n-60) for n>67
%e A207513 Some solutions for n=4
%e A207513 ..1..1..1..0..0..1..0....0..1..0..1..0..0..1....1..1..1..1..0..1..0
%e A207513 ..1..0..0..1..0..0..1....0..0..1..0..0..1..0....1..1..0..1..0..0..1
%e A207513 ..0..0..1..0..0..1..0....0..1..0..1..0..0..1....0..0..1..0..0..1..0
%e A207513 ..1..0..0..1..0..0..1....0..0..1..0..0..1..0....1..1..1..1..0..0..1
%K A207513 nonn
%O A207513 1,1
%A A207513 _R. H. Hardin_ Feb 18 2012