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A157554 Half the number of length n integer sequences with sum zero and sum of squares 968. 1
1, 3, 66, 3990, 178335, 6510483, 190667659, 5047394427, 131071431060, 3262733109790, 78872812374741, 1857536871457917, 41896936373100900, 899337065318075790, 18460566561637223550, 365127965985604164628 (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,0,968)/2.
CROSSREFS
Sequence in context: A368596 A157984 A187547 * A185053 A165655 A157576
KEYWORD
nonn
AUTHOR
R. H. Hardin Mar 02 2009
STATUS
approved

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Last modified May 26 19:46 EDT 2024. Contains 372844 sequences. (Running on oeis4.)