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A157587
Half the number of length n integer sequences with sum zero and sum of squares 6050.
1
1, 3, 462, 41230, 2595765, 186323823, 13994329244, 1089068168952, 80599569668955, 5296880405561547, 320164718544367950, 18262041337319290446, 998477188502752352485, 52770671879708445120045, 2707901917377956941817496
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,0,6050)/2.
CROSSREFS
Sequence in context: A157601 A094454 A261004 * A054702 A140015 A342067
KEYWORD
nonn
AUTHOR
R. H. Hardin Mar 02 2009
STATUS
approved