A183929 - OEIS

%I #5 Mar 31 2012 12:35:55

%S 1,2,5,11,21,36,60,95,143,212,302,424,582,784,1034,1355,1736,2207,

%T 2776,3455,4252,5213,6315,7607,9105,10826,12786,15053,17595,20488,

%U 23752,27416,31497,36092,41169,46821,53078,59989,67574,75963,85103,95134,106094

%N Number of nondecreasing arrangements of n numbers in -3..3 with sum zero and sum of squares less than n*12/3

%C Column 3 of A183935

%H R. H. Hardin, <a href="/A183929/b183929.txt">Table of n, a(n) for n = 1..200</a>

%F Empirical: a(n)=2*a(n-1)-a(n-2)-a(n-5)+2*a(n-6)-a(n-7)+a(n-8)-a(n-9)-a(n-10)+a(n-11)+a(n-13)-a(n-14)-a(n-16)+2*a(n-18)-a(n-19)+a(n-20)-2*a(n-21)+a(n-23)+a(n-24)-a(n-25)-a(n-28)+2*a(n-29)-a(n-30)-a(n-33)+2*a(n-34)-a(n-35)-a(n-38)+a(n-39)+a(n-40)-2*a(n-42)+a(n-43)-a(n-44)+2*a(n-45)-a(n-47)-a(n-49)+a(n-50)+a(n-52)-a(n-53)-a(n-54)+a(n-55)-a(n-56)+2*a(n-57)-a(n-58)-a(n-61)+2*a(n-62)-a(n-63)

%e All solutions for n=4

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

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

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

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

%K nonn

%O 1,2

%A _R. H. Hardin_ Jan 08 2011