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%I
%S 7,37,153,651,2771,11817,50391,214867,916173,3906507,16657167,
%T 71025391,302848889,1291333199,5506183213,23478102983,100109512887,
%U 426862194475,1820120064499,7760905257671,33092130346043,141103267528637
%N Number of -3..3 arrays of n elements with first and second differences also in -3..3.
%C Column 3 of A201088.
%H R. H. Hardin, <a href="/A201083/b201083.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 4*a(n-1) -a(n-2) +8*a(n-3) +4*a(n-4) +3*a(n-5) -2*a(n-6) -3*a(n-7) -7*a(n-8) -4*a(n-9) +7*a(n-10) +8*a(n-11) +3*a(n-12) -3*a(n-13) -2*a(n-14) +a(n-15) +2*a(n-16) +a(n-17).
%e Some solutions for n=7
%e ..0...-1...-2...-3....1....1...-3....3....2....0....0....2....2...-2....2....0
%e ..0...-1....0...-3....0....2....0....1....3....3....3....1...-1...-2....2....1
%e .-1....2....3...-1....0....1....0...-1....2....3....3....1...-1...-1...-1....0
%e .-3....3....3....0....3....0...-1...-2....1....0....2....2...-1....2...-2....1
%e .-3....1....3....2....3...-2...-1....0....2....0....3....0....1....2...-1....0
%e .-2....1....0....1....3...-1....2....1....2....1....1...-2....0....2....2...-2
%e .-1....1...-3...-2....0....0....2....3....1....0....1...-2....2...-1....2...-2
%Y Cf. A201088.
%K nonn
%O 1,1
%A _R. H. Hardin_ Nov 26 2011
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