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A157576 Half the number of length n integer sequences with sum zero and sum of squares 3872. 1
1, 3, 66, 14630, 1446495, 105717843, 6111518987, 323657828739, 16777260176400, 835056998169955, 40377792647031081, 1902059925519314067, 85804943707548960986, 3683698658760163764945, 151229533594426205964390 (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,0,3872)/2.
CROSSREFS
Sequence in context: A157554 A185053 A165655 * A339599 A105443 A065425
KEYWORD
nonn
AUTHOR
R. H. Hardin Mar 02 2009
STATUS
approved

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Last modified June 19 03:10 EDT 2024. Contains 373492 sequences. (Running on oeis4.)