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%I #17 Mar 31 2012 12:36:53
%S 2,6,20,36,62,90,128,168,218,270,332,396,470,546,632,720,818,918,1028,
%T 1140,1262,1386,1520,1656,1802,1950,2108,2268,2438,2610,2792,2976,
%U 3170,3366,3572,3780,3998,4218,4448,4680,4922,5166,5420,5676,5942,6210,6488
%N Number of arrays of 3 integers in -n..n with sum zero and adjacent elements differing in absolute value
%C Row 1 of A202962
%H R. H. Hardin, <a href="/A202963/b202963.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 2*a(n-1) -2*a(n-3) +a(n-4). [Hardin]
%F Empirical: G.f. x*(2+2*x+8*x^2)/(1-2*x+2*x^3-x^4). [Colin Barker, Jan 04 2012]
%e Some solutions for n=5
%e .-2....1....3...-4...-2...-4....5...-1...-1....2....2....2...-2....2....1....4
%e .-3....0....1....1...-1....3...-1....5....2...-4....0....1....3....3...-2...-1
%e ..5...-1...-4....3....3....1...-4...-4...-1....2...-2...-3...-1...-5....1...-3
%K nonn
%O 1,1
%A _R. H. Hardin_ Dec 26 2011
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