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A157599
Half the number of length n integer sequences with sum zero and sum of squares 8978.
1
1, 9, 402, 44230, 4512465, 423267831, 37803628716, 3527887213476, 318332583745245, 25647872392849575, 1892012326768856754, 131465592083214083058, 8752726227773492626389, 563521423775802944905950
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,0,8978)/2.
CROSSREFS
Sequence in context: A012078 A332139 A266924 * A063876 A063156 A058850
KEYWORD
nonn
AUTHOR
R. H. Hardin Mar 02 2009
STATUS
approved