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%I #5 Mar 31 2012 12:36:34
%S 2,12,12,76,206,76,492,3838,3838,492,3212,74582,213328,74582,3212,
%T 21036,1481214,12510524,12510524,1481214,21036,137932,29737425,
%U 757941274,2223874372,757941274,29737425,137932,904812,600187403,46796529288
%N T(n,k)=Number of 2nX2k 0..2 arrays with values 0..2 introduced in row major order and each element equal to exactly one horizontal or vertical neighbor
%C Table starts
%C ......2........12..........76..........492.........3212..........21036
%C .....12.......206........3838........74582......1481214.......29737425
%C .....76......3838......213328.....12510524....757941274....46796529288
%C ....492.....74582....12510524...2223874372.411119156729.77956630302044
%C ...3212...1481214...757941274.411119156729
%C ..21036..29737425.46796529288
%C .137932.600187403
%C .904812
%H R. H. Hardin, <a href="/A198532/b198532.txt">Table of n, a(n) for n = 1..40</a>
%e Some solutions for n=5 k=3
%e ..0..0..1..1..0..0....0..0..1..1..0..0....0..0..1..1..0..0....0..0..1..1..0..0
%e ..1..1..0..0..1..1....1..1..0..0..1..1....1..1..0..0..1..1....1..1..0..0..1..1
%e ..0..0..1..1..0..0....0..0..1..1..0..0....0..0..1..1..0..0....0..0..1..1..0..0
%e ..1..1..0..0..2..1....1..1..0..0..1..1....1..1..0..0..1..1....1..1..0..0..2..2
%e ..0..0..1..1..2..1....0..0..1..1..2..2....0..0..1..1..0..2....0..0..1..1..0..0
%e ..1..1..0..0..1..2....1..1..2..0..1..1....1..1..2..2..0..2....2..1..0..0..2..2
%e ..0..0..2..2..1..2....0..0..2..0..2..0....0..2..0..1..2..1....2..1..2..1..0..1
%e ..1..1..0..1..2..1....2..2..1..1..2..0....0..2..0..1..2..1....0..0..2..1..0..1
%e ..2..2..0..1..2..1....1..0..2..2..1..1....2..0..1..2..0..2....1..2..1..0..2..2
%e ..0..0..2..2..0..0....1..0..1..1..2..2....2..0..1..2..0..2....1..2..1..0..1..1
%Y Column 1 is A198474
%K nonn,tabl
%O 1,1
%A _R. H. Hardin_ Oct 26 2011