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%I #11 May 04 2018 05:18:42
%S 7,12,18,27,39,53,69,87,107,129,153,179,207,237,269,303,339,377,417,
%T 459,503,549,597,647,699,753,809,867,927,989,1053,1119,1187,1257,1329,
%U 1403,1479,1557,1637,1719,1803,1889,1977,2067,2159,2253,2349,2447,2547,2649
%N Number of nondecreasing arrangements of n+2 numbers in 0..4 with the last equal to 4 and each after the second equal to the sum of one or two of the preceding three.
%C Column 4 of A190041.
%H R. H. Hardin, <a href="/A190036/b190036.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = n^2 + 3*n - 1 for n>3.
%F Conjectures from _Colin Barker_, May 04 2018: (Start)
%F G.f.: x*(7 - 9*x + 3*x^2 + 2*x^3 - x^5) / (1 - x)^3.
%F a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) for n>4.
%F (End)
%e Some solutions for n=3:
%e 2 1 1 3 1 2 0 1 0 1 1 2 0 1 1 4
%e 2 1 1 4 4 2 2 2 2 3 2 2 4 2 3 4
%e 4 2 2 4 4 2 2 2 2 3 2 2 4 3 4 4
%e 4 2 3 4 4 4 2 2 4 4 4 2 4 4 4 4
%e 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4
%Y Cf. A190041.
%K nonn
%O 1,1
%A _R. H. Hardin_, May 04 2011
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