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Number of n X 5 binary arrays with each 1 adjacent to exactly two 0's.
1

%I #7 Apr 05 2020 21:46:15

%S 5,49,194,899,4643,21708,104651,506385,2433550,11727959,56508374,

%T 272163366,1311142020,6316072899,30425539496,146567346229,

%U 706046292084,3401176547138,16384217757962,78926341085721,380205390786374

%N Number of n X 5 binary arrays with each 1 adjacent to exactly two 0's.

%C Column 5 of A183335.

%H R. H. Hardin, <a href="/A183333/b183333.txt">Table of n, a(n) for n = 1..106</a>

%F Empirical: a(n)=5*a(n-1)-6*a(n-2)+28*a(n-3)-29*a(n-4)+78*a(n-5)-86*a(n-6)+80*a(n-7)-39*a(n-8)-639*a(n-9)+566*a(n-10)-503*a(n-11)-523*a(n-12)+1335*a(n-13)-182*a(n-14)+1071*a(n-15)+1059*a(n-16)-1447*a(n-17)-502*a(n-18)-534*a(n-19)-3*a(n-20)+644*a(n-21)+713*a(n-22)+1436*a(n-23)-999*a(n-24)-1937*a(n-25)-3051*a(n-26)-1799*a(n-27)+3118*a(n-28)+2735*a(n-29)+645*a(n-30)-582*a(n-31)-405*a(n-32)+280*a(n-33)-306*a(n-34)-222*a(n-35)-48*a(n-36)-41*a(n-37)+101*a(n-38)-14*a(n-39)-5*a(n-40)-6*a(n-41)+4*a(n-42)+3*a(n-43).

%e Some solutions for 7 X 5

%e ..0..0..1..0..1....0..0..0..0..0....0..0..0..0..1....1..0..0..0..0

%e ..1..0..1..1..0....1..1..0..0..0....1..1..0..0..0....0..0..0..1..1

%e ..1..0..0..1..0....0..1..1..1..1....0..1..0..0..0....1..1..1..1..0

%e ..0..0..0..1..0....0..0..0..0..0....0..1..1..1..1....0..0..0..0..0

%e ..0..0..1..1..0....1..0..1..1..0....1..0..0..0..0....0..0..0..0..0

%e ..0..0..1..0..0....1..0..1..1..0....1..0..0..0..0....0..0..0..0..0

%e ..1..0..1..0..0....0..0..0..0..0....0..0..1..1..0....0..0..0..0..1

%K nonn

%O 1,1

%A _R. H. Hardin_ Jan 03 2011