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%I #8 Apr 05 2018 10:27:29
%S 5,14,38,70,111,162,224,298,385,486,602,734,883,1050,1236,1442,1669,
%T 1918,2190,2486,2807,3154,3528,3930,4361,4822,5314,5838,6395,6986,
%U 7612,8274,8973,9710,10486,11302,12159,13058,14000,14986,16017,17094,18218,19390
%N Number of nondecreasing arrangements of n+3 numbers in 0..3 with each number being the sum mod 4 of three others.
%C Column 3 of A183904.
%H R. H. Hardin, <a href="/A183898/b183898.txt">Table of n, a(n) for n = 1..62</a>
%F Empirical: a(n) = (1/6)*n^3 + (5/2)*n^2 + (25/3)*n - 14 for n>1.
%F Conjectures from _Colin Barker_, Apr 05 2018: (Start)
%F G.f.: x*(5 - 6*x + 12*x^2 - 18*x^3 + 8*x^4) / (1 - x)^4.
%F a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4) for n>5.
%F (End)
%e All solutions for n=2:
%e ..0....2....0....1....0....0....1....1....0....0....0....1....0....0
%e ..2....2....0....3....1....0....1....1....0....0....1....1....1....0
%e ..2....2....2....3....1....0....3....1....2....0....2....1....1....1
%e ..3....2....3....3....2....0....3....3....2....2....3....1....2....1
%e ..3....2....3....3....3....0....3....3....2....2....3....3....2....2
%Y Cf. A183904.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 07 2011
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