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T(n,k)=Half the number of nXk binary arrays with every element equal to exactly one or two of its horizontal and vertical neighbors
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%I #7 Mar 31 2012 12:36:03

%S 0,1,1,1,3,1,2,10,10,2,3,23,30,23,3,5,61,118,118,61,5,8,162,393,514,

%T 393,162,8,13,421,1430,2398,2398,1430,421,13,21,1103,5004,11789,15782,

%U 11789,5004,1103,21,34,2890,17877,54223,98975,98975,54223,17877,2890,34,55

%N T(n,k)=Half the number of nXk binary arrays with every element equal to exactly one or two of its horizontal and vertical neighbors

%C Table starts

%C ..0....1......1.......2.........3..........5............8............13

%C ..1....3.....10......23........61........162..........421..........1103

%C ..1...10.....30.....118.......393.......1430.........5004.........17877

%C ..2...23....118.....514......2398......11789........54223........257050

%C ..3...61....393....2398.....15782......98975.......649826.......4143707

%C ..5..162...1430...11789.....98975.....923808......7678409......68363184

%C ..8..421...5004...54223....649826....7678409.....91052720....1073661088

%C .13.1103..17877..257050...4143707...68363184...1073661088...17200095426

%C .21.2890..63181.1213538..26679121..593948668..12644950311..278159538826

%C .34.7563.224324.5716561.171597547.5187350050.149729950026.4418356392225

%H R. H. Hardin, <a href="/A185835/b185835.txt">Table of n, a(n) for n = 1..219</a>

%e Some solutions for 5X4 with a(1,1)=0

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

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

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

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

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

%Y Column 1 is A000045(n-1)

%K nonn,tabl

%O 1,5

%A _R. H. Hardin_ Feb 05 2011