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Number of nX7 0..1 arrays with no element equal to exactly two horizontal and vertical neighbors, with new values 0..1 introduced in row major order
1

%I #4 Apr 06 2014 21:28:24

%S 21,86,515,3765,28942,231665,1906245,16000486,135790448,1158315893,

%T 9946076742,85823282205,743139183617,6451236349918,56119492560507,

%U 488978060398481,4265874977466648,37250999894755072,325525391487428809

%N Number of nX7 0..1 arrays with no element equal to exactly two horizontal and vertical neighbors, with new values 0..1 introduced in row major order

%C Column 7 of A240519

%H R. H. Hardin, <a href="/A240518/b240518.txt">Table of n, a(n) for n = 1..169</a>

%e Some solutions for n=4

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Apr 06 2014