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%I #7 Sep 23 2014 17:10:59
%S 48,90,172,334,656,1300,2584,5148,10272,20520,41008,81976,163904,
%T 327760,655456,1310832,2621568,5243040,10485952,20971744,41943296,
%U 83886400,167772544,335544768,671089152,1342177920,2684355328,5368710016
%N Number of length n+3 0..2 arrays with no disjoint pairs in any consecutive four terms having the same sum
%C Column 2 of A247726
%H R. H. Hardin, <a href="/A247720/b247720.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 2*a(n-1) +2*a(n-4) -4*a(n-5).
%F Empirical G.f.: -2*x*(-24+3*x+4*x^2+5*x^3+54*x^4) / ( (2*x-1)*(2*x^4-1) ). - _R. J. Mathar_, Sep 23 2014
%e Some solutions for n=6
%e ..1....2....2....2....2....2....1....0....2....2....1....0....1....0....1....2
%e ..0....1....0....0....0....0....0....0....0....2....2....2....2....2....0....2
%e ..0....0....1....2....2....0....0....2....1....2....0....2....0....2....2....1
%e ..0....0....2....1....1....1....2....0....2....0....0....1....2....1....0....2
%e ..1....0....0....0....2....0....1....1....0....2....1....2....2....2....0....2
%e ..0....1....0....2....2....2....2....0....0....2....2....2....2....0....0....0
%e ..0....2....0....0....2....2....0....2....1....1....0....0....1....0....1....1
%e ..2....0....1....1....0....1....2....0....0....0....2....1....2....1....0....2
%e ..1....2....0....0....1....2....2....0....0....2....2....2....2....2....2....0
%K nonn
%O 1,1
%A _R. H. Hardin_, Sep 23 2014
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