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A157553 Half the number of length n integer sequences with sum zero and sum of squares 882. 1
1, 9, 162, 3010, 100035, 3757383, 119414988, 3493064772, 95851672965, 2417802179815, 55917688232274, 1207875284200806, 25067626930769059, 505877445756815265, 9921228112937485800, 188795923012791958280 (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,0,882)/2.
CROSSREFS
Sequence in context: A158749 A300843 A133681 * A202438 A237024 A156273
KEYWORD
nonn
AUTHOR
R. H. Hardin Mar 02 2009
STATUS
approved

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Last modified May 22 19:06 EDT 2024. Contains 372758 sequences. (Running on oeis4.)