A200759 - OEIS

%I #14 Feb 14 2018 03:16:54

%S 4,10,23,51,110,233,488,1013,2088,4278,8720,17695,35768,72054,144717,

%T 289887,579312,1155257,2299426,4568935,9064316,17957296,35529320,

%U 70213565,138607340,273351142,538591471,1060310343,2085784818,4100099321

%N Number of 0..3 arrays x(0..n-1) of n elements with nondecreasing average value

%C Column 3 of A200763

%H R. H. Hardin, <a href="/A200759/b200759.txt">Table of n, a(n) for n = 1..174</a>

%F Empirical: a(n) = 5*a(n-1) -8*a(n-2) +3*a(n-3) +3*a(n-4) -2*a(n-5) +a(n-6) -3*a(n-7) +2*a(n-8) -a(n-9) +a(n-10).

%F Empirical g.f.: -x*(4-10*x+5*x^2+4*x^3-3*x^4-3*x^6+x^9+2*x^7-x^8) / ( (x-1)*(x^3+x^2+x-1)*(x^6-x^5+2*x^4-x^3-2*x^2+3*x-1) ). - _R. J. Mathar_, Nov 22 2011

%e Some solutions for n=8

%e ..0....0....1....0....0....0....0....0....1....0....0....0....0....0....0....0

%e ..0....0....1....3....0....0....2....0....2....0....0....0....0....2....2....0

%e ..0....0....1....3....3....2....1....1....2....3....1....0....1....3....1....0

%e ..0....2....1....2....2....2....1....1....2....3....1....3....2....2....2....3

%e ..0....2....1....2....2....3....1....1....2....2....3....1....1....3....3....1

%e ..0....2....2....2....3....3....2....3....3....3....3....2....3....3....2....2

%e ..1....1....3....2....2....2....2....1....3....2....3....1....2....3....2....1

%e ..3....3....3....2....2....2....2....1....3....2....3....3....2....3....3....1

%K nonn

%O 1,1

%A _R. H. Hardin_, Nov 22 2011