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A157555
Half the number of length n integer sequences with sum zero and sum of squares 1058.
1
1, 3, 150, 5070, 182175, 5887791, 180232444, 5773910724, 178835952285, 4946264437455, 125256800641170, 2987737855296558, 68285219070825029, 1509200139206357640, 32387266774022554680, 675011623200542959496
OFFSET
2,2
LINKS
FORMULA
[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,0,1058)/2.
CROSSREFS
Sequence in context: A181748 A118840 A111816 * A157578 A137802 A100203
KEYWORD
nonn
AUTHOR
R. H. Hardin Mar 02 2009
STATUS
approved