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A157552 Half the number of length n integer sequences with sum zero and sum of squares 800. 1
1, 3, 42, 3410, 143445, 4303761, 117586819, 2875510809, 67804504560, 1524258428187, 33435072500775, 715914503534022, 14685555146992730, 286576099225123995, 5347457520977926782, 96148425385860533358 (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,0,800)/2.
CROSSREFS
Sequence in context: A083402 A145984 A213956 * A058808 A155210 A157572
KEYWORD
nonn
AUTHOR
R. H. Hardin Mar 02 2009
STATUS
approved

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Last modified May 27 13:56 EDT 2024. Contains 372861 sequences. (Running on oeis4.)