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%I #11 Nov 07 2018 14:42:49
%S 33,45,61,81,105,153,217,297,393,585,841,1161,1545,2313,3337,4617,
%T 6153,9225,13321,18441,24585,36873,53257,73737,98313,147465,213001,
%U 294921,393225,589833,851977,1179657,1572873,2359305,3407881,4718601,6291465
%N Number of length n+3 0..2 arrays with some disjoint pairs in every consecutive four terms having the same sum.
%H R. H. Hardin, <a href="/A247527/b247527.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-1) + 4*a(n-4) - 4*a(n-5).
%F Empirical g.f.: x*(33 + 12*x + 16*x^2 + 20*x^3 - 108*x^4) / ((1 - x)*(1 - 2*x^2)*(1 + 2*x^2)). - _Colin Barker_, Nov 07 2018
%e Some solutions for n=6:
%e ..2....1....0....2....0....2....0....0....1....1....0....0....2....1....1....2
%e ..1....0....1....1....1....1....1....1....0....1....2....0....1....2....2....1
%e ..0....2....0....0....0....1....1....1....2....0....1....1....1....0....2....1
%e ..1....1....1....1....1....0....0....0....1....2....1....1....2....1....1....2
%e ..2....1....2....2....2....2....0....0....1....1....2....2....0....1....1....0
%e ..1....0....1....1....1....1....1....1....2....1....2....2....1....2....0....1
%e ..2....2....2....0....2....1....1....1....0....2....1....1....1....0....2....1
%e ..1....1....1....1....1....0....0....0....1....2....1....1....2....1....1....0
%e ..2....1....0....0....2....2....2....0....1....1....0....0....0....1....1....2
%Y Column 2 of A247533.
%K nonn
%O 1,1
%A _R. H. Hardin_, Sep 18 2014
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