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%I #4 Feb 12 2016 08:45:08
%S 20,420,7831,128232,1971414,29134076,418632185,5894815754,81718671716,
%T 1119014223138,15171181272721,203998929406004,2724149465085496,
%U 36163754541884778,477648079847735215,6280858615510607492
%N Number of nX6 binary arrays with some 1 horizontally or vertically adjacent to some other 1 exactly once.
%C Column 6 of A268740.
%H R. H. Hardin, <a href="/A268738/b268738.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 16*a(n-1) +60*a(n-2) -1148*a(n-3) -3346*a(n-4) +16272*a(n-5) +36588*a(n-6) -104246*a(n-7) -147989*a(n-8) +349140*a(n-9) +217324*a(n-10) -591448*a(n-11) -19320*a(n-12) +431032*a(n-13) -151921*a(n-14) -73194*a(n-15) +41684*a(n-16) +2552*a(n-17) -3594*a(n-18) +148*a(n-19) +100*a(n-20) -4*a(n-21) -a(n-22)
%e Some solutions for n=4
%e ..0..0..0..0..1..0. .0..0..0..0..1..0. .1..0..0..0..0..1. .0..0..1..1..0..0
%e ..0..0..1..0..0..0. .0..1..0..0..0..0. .0..1..0..0..0..0. .0..1..0..0..1..0
%e ..1..0..0..0..0..0. .1..0..0..0..0..0. .1..0..0..1..0..0. .0..0..0..0..0..0
%e ..0..0..1..1..0..0. .1..0..1..0..1..0. .1..0..0..0..0..1. .0..0..0..0..0..1
%Y Cf. A268740.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 12 2016
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