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A268013 Number of n X 1 0..2 arrays with every repeated value in every row and column greater than or equal to the previous repeated value.

%I A268013 #8 Feb 26 2018 05:53:36
%S A268013 3,9,27,78,222,622,1722,4719,12821,34575,92637,246788,654120,1725900,
%T A268013 4535172,11872941,30977943,80575109,208983471,540606474,1395061474,
%U A268013 3591893274,9228660318,23664610747,60570324105,154763821419,394795932561
%N A268013 Number of n X 1 0..2 arrays with every repeated value in every row and column greater than or equal to the previous repeated value.
%C A268013 Column 1 of A268019.
%H A268013 R. H. Hardin, <a href="/A268013/b268013.txt">Table of n, a(n) for n = 1..210</a>
%F A268013 Empirical: a(n) = 6*a(n-1) - 9*a(n-2) - 4*a(n-3) + 9*a(n-4) + 6*a(n-5) + a(n-6).
%F A268013 Empirical g.f.: x*(3 - 9*x + 9*x^3 + 6*x^4 + x^5) / (1 - 2*x - x^2)^3. - _Colin Barker_, Feb 26 2018
%e A268013 Some solutions for n=8:
%e A268013 ..1....2....2....1....2....1....0....0....2....1....2....0....2....2....2....2
%e A268013 ..0....1....2....2....0....1....0....0....0....0....0....2....1....0....0....0
%e A268013 ..2....1....2....0....0....2....1....1....2....1....2....0....2....2....0....2
%e A268013 ..0....1....2....2....0....2....0....2....0....1....0....0....0....0....1....2
%e A268013 ..0....0....0....2....2....1....0....2....2....2....2....1....0....1....0....0
%e A268013 ..1....2....1....1....1....0....2....0....2....2....1....1....0....2....1....2
%e A268013 ..1....1....2....2....2....2....2....2....0....0....0....2....0....2....2....2
%e A268013 ..2....1....1....0....0....1....0....1....1....2....0....0....0....1....0....1
%Y A268013 Cf. A268019.
%K A268013 nonn
%O A268013 1,1
%A A268013 _R. H. Hardin_, Jan 24 2016