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%I #8 Nov 12 2018 14:36:57
%S 5,33,211,1269,7109,37881,195927,996933,5029417,25262121,126608171,
%T 633821781,3171197325,15861685497,79324281727,396666275397,
%U 1983460173617,9917674841193,49589469690579,247950578857365,1239762467069077
%N Number of length n+1 0..4 arrays with the sum of adjacent differences multiplied by some arrangement of +-1 equal to zero.
%H R. H. Hardin, <a href="/A250163/b250163.txt">Table of n, a(n) for n = 1..55</a>
%F Empirical: a(n) = 16*a(n-1) -105*a(n-2) +372*a(n-3) -783*a(n-4) +1008*a(n-5) -779*a(n-6) +332*a(n-7) -60*a(n-8).
%F Empirical g.f.: x*(5 - 47*x + 208*x^2 - 502*x^3 + 599*x^4 - 311*x^5 + 52*x^6 + 44*x^7) / ((1 - x)^4*(1 - 2*x)^2*(1 - 3*x)*(1 - 5*x)). - _Colin Barker_, Nov 12 2018
%e Some solutions for n=6:
%e ..3....0....1....0....1....2....0....4....4....4....1....3....4....1....1....0
%e ..2....1....0....0....2....3....4....1....4....3....1....0....2....3....3....4
%e ..3....1....4....2....3....2....0....0....1....0....3....2....4....4....0....3
%e ..2....2....2....1....3....0....0....0....0....0....4....4....1....2....4....0
%e ..0....0....4....3....1....4....3....1....4....2....4....1....3....4....3....1
%e ..2....0....2....1....3....0....1....2....2....2....3....2....2....3....2....2
%e ..3....2....3....0....3....0....2....2....4....0....1....3....0....3....1....2
%Y Column 4 of A250167.
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 13 2014
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