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%I #9 Nov 14 2018 07:18:40
%S 5,17,38,125,335,1061,3069,9495,28221,86149,258252,782393,2350442,
%T 7090347,21303611,64109181,192553620,578665211,1737374865,5217197093,
%U 15659477401,47004010481,141055441813,423295193635,1270118805510
%N Number of length n+1 0..2 arrays with the sum of the minimum of each adjacent pair multiplied by some arrangement of +-1 equal to zero.
%H R. H. Hardin, <a href="/A250413/b250413.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 6*a(n-1) - 3*a(n-2) - 40*a(n-3) + 59*a(n-4) + 68*a(n-5) - 146*a(n-6) - 14*a(n-7) + 91*a(n-8) - 8*a(n-9) - 12*a(n-10).
%F Empirical g.f.: x*(5 - 13*x - 49*x^2 + 148*x^3 + 84*x^4 - 397*x^5 + 40*x^6 + 257*x^7 - 36*x^8 - 36*x^9) / ((1 - x)*(1 - 2*x)*(1 + 2*x)*(1 - 3*x)*(1 - 2*x - x^2 + x^3)*(1 - 3*x^2 - x^3)). - _Colin Barker_, Nov 14 2018
%e Some solutions for n=6:
%e ..2....0....1....2....2....2....2....2....0....2....2....0....1....0....2....1
%e ..2....0....2....0....1....1....0....1....1....2....0....0....1....0....0....2
%e ..1....0....1....2....0....0....1....1....2....1....1....1....0....1....2....1
%e ..2....2....1....2....2....0....0....0....2....2....1....1....1....1....1....2
%e ..1....0....2....2....2....0....0....0....0....2....0....1....2....2....0....0
%e ..2....2....2....1....1....1....2....0....1....0....1....0....1....2....1....2
%e ..0....0....2....1....0....1....0....1....2....0....1....0....2....2....1....1
%Y Column 2 of A250419.
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 22 2014
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