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%I #8 May 02 2018 09:03:11
%S 2,8,11,20,21,36,31,49,42,63,51,79,60,93,72,105,80,125,89,133,104,149,
%T 109,168,117,178,135,190,138,213,147,219,166,234,166,257,176,263,197,
%U 274,196,303,205,304,227,319,225,346,234,347,259,360,254,392,262,389,290,404
%N Number of nondecreasing arrangements of 5 numbers in 0..n with the last equal to n and each after the second equal to the sum of one or two of the preceding four.
%C Row 3 of A189326.
%H R. H. Hardin, <a href="/A189328/b189328.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = -3*a(n-1) -5*a(n-2) -5*a(n-3) -2*a(n-4) +3*a(n-5) +8*a(n-6) +10*a(n-7) +8*a(n-8) +3*a(n-9) -2*a(n-10) -5*a(n-11) -5*a(n-12) -3*a(n-13) -a(n-14).
%F Empirical g.f.: x*(2 + 14*x + 45*x^2 + 103*x^3 + 180*x^4 + 264*x^5 + 326*x^6 + 350*x^7 + 322*x^8 + 258*x^9 + 173*x^10 + 97*x^11 + 40*x^12 + 11*x^13) / ((1 - x)^2*(1 + x)^2*(1 + x^2)*(1 + x + x^2)^2*(1 + x + x^2 + x^3 + x^4)). - _Colin Barker_, May 02 2018
%e All solutions for n=3:
%e ..1....1....1....1....0....1....3....0....2....1....1
%e ..2....2....3....2....1....1....3....3....3....1....1
%e ..2....2....3....3....1....2....3....3....3....2....1
%e ..3....2....3....3....2....3....3....3....3....2....2
%e ..3....3....3....3....3....3....3....3....3....3....3
%Y Cf. A189326.
%K nonn
%O 1,1
%A _R. H. Hardin_, Apr 20 2011
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