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A221188 T(n,k)=Equals two maps: number of nXk binary arrays indicating the locations of corresponding elements equal to exactly two of their horizontal, vertical and antidiagonal neighbors in a random 0..2 nXk array 3

%I

%S 1,1,1,2,6,2,4,27,27,4,7,107,274,107,7,12,461,2648,2648,461,12,21,

%T 1844,23765,51924,23765,1844,21,37,7502,203122,928133,928133,203122,

%U 7502,37,65,29893,1686374,15638551,32233374,15638551,1686374,29893,65,114,119342

%N T(n,k)=Equals two maps: number of nXk binary arrays indicating the locations of corresponding elements equal to exactly two of their horizontal, vertical and antidiagonal neighbors in a random 0..2 nXk array

%C Table starts

%C ..1.....1.......2........4........7.......12........21.......37.....65.114

%C ..1.....6......27......107......461.....1844......7502....29893.119342

%C ..2....27.....274.....2648....23765...203122...1686374.13787513

%C ..4...107....2648....51924...928133.15638551.256020803

%C ..7...461...23765...928133.32233374

%C .12..1844..203122.15638551

%C .21..7502.1686374

%C .37.29893

%C .65

%H R. H. Hardin, <a href="/A221188/b221188.txt">Table of n, a(n) for n = 1..49</a>

%e Some solutions for n=3 k=4

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

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

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

%Y Column 1 is A005251(n+1)

%Y Column 2 is A220529

%K nonn,tabl

%O 1,4

%A _R. H. Hardin_ Jan 04 2013

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Last modified February 18 21:20 EST 2020. Contains 332028 sequences. (Running on oeis4.)