%I #4 Mar 31 2012 12:35:25
%S 1,3,246,17230,1034445,59305701,3243926588,185256960120,
%T 10229264210745,504340200498475,22766981281651398,968060807776968126,
%U 39440547846380819957,1553885734839506217555,59443252831855326838200
%N Half the number of length n integer sequences with sum zero and sum of squares 3362.
%H R. H. Hardin, <a href="/A157573/b157573.txt">Table of n, a(n) for n=2..50</a>
%F [cache enabling] count(n,s,ss)->count(n,t,tt) where t=s mod n, q=(t-s)/n, tt=ss+2*q*s+n*q^2; count(n,t,tt)=sum[i^2<=tt]{ count(n-1,t-i,tt-i^2) }. a(n)=count(n,0,3362)/2.
%K nonn
%O 2,2
%A _R. H. Hardin_ Mar 02 2009