%I
%S 1,3,102,8190,665685,36705753,1679350127,68733531189,2760184991340,
%T 106183264044550,3966764429800029,144378604643078598,
%U 5032695166253713140,166954292511159130110,5296343179095984782250,161894623559389026065130
%N Half the number of length n integer sequences with sum zero and sum of squares 2312.
%H R. H. Hardin, <a href="/A157566/b157566.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,0,2312)/2.
%K nonn
%O 2,2
%A _R. H. Hardin_ Mar 02 2009
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