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%I #4 Dec 27 2014 09:32:16
%S 7,53,90,393,952,3323,9205,29445,85717,264455,784350,2382673,7116997,
%T 21472661,64312410,193442021,579975177,1742036675,5224994385,
%U 15683870729,47048349217,141182669949,423540081615,1270780266933,3812331343012
%N Number of length n+2 0..2 arrays with the sum of medians of adjacent triples multiplied by some arrangement of +-1 equal to zero
%C Column 2 of A253129
%H R. H. Hardin, <a href="/A253123/b253123.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 6*a(n-1) -7*a(n-2) -17*a(n-3) +45*a(n-4) -57*a(n-5) +64*a(n-6) +44*a(n-7) -186*a(n-8) +205*a(n-9) -290*a(n-10) +290*a(n-11) -196*a(n-12) +161*a(n-13) -77*a(n-14) +28*a(n-15) -12*a(n-16)
%e Some solutions for n=9
%e ..2....0....2....1....0....0....1....1....0....1....0....2....0....2....1....2
%e ..2....0....0....2....0....1....2....0....2....0....2....2....1....1....0....0
%e ..2....2....2....1....1....2....0....2....2....1....0....1....1....1....1....0
%e ..2....1....2....0....1....2....0....1....2....1....2....0....2....2....0....1
%e ..0....0....1....1....0....1....1....0....0....0....2....0....1....1....2....0
%e ..0....1....0....2....0....1....0....1....2....1....0....0....0....2....1....2
%e ..1....1....1....0....2....1....2....0....2....2....0....0....2....2....1....0
%e ..2....1....1....2....1....1....2....0....0....0....0....2....0....1....0....1
%e ..2....2....1....1....2....0....2....2....0....2....1....1....1....2....0....1
%e ..1....2....1....0....1....2....0....0....0....1....1....1....1....0....1....0
%e ..0....0....1....1....2....2....0....2....1....1....2....1....0....2....2....0
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 27 2014
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