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A157571 Half the number of length n integer sequences with sum zero and sum of squares 3042. 1
1, 9, 270, 10990, 622725, 43526469, 2629049500, 142957923228, 7300452572415, 342254197570615, 14695487432860410, 589524950365892190, 22721530823371062501, 851515705898338365990, 31013728074479042288280 (list; graph; refs; listen; history; text; internal format)
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,0,3042)/2.
CROSSREFS
Sequence in context: A168600 A088672 A300169 * A202689 A364438 A218693
KEYWORD
nonn
AUTHOR
R. H. Hardin Mar 02 2009
STATUS
approved

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Last modified March 28 10:55 EDT 2024. Contains 371241 sequences. (Running on oeis4.)