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A157596 Half the number of length n integer sequences with sum zero and sum of squares 8192. 1
1, 3, 6, 27310, 4493895, 469762041, 39763084319, 3062924462367, 231122336887800, 16732612596774745, 1176767971442596731, 80630592887297229153, 5290690279278336041746, 330378602282944731759075 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,2

LINKS

R. H. Hardin, Table of n, a(n) for n=2..50

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,0,8192)/2.

CROSSREFS

Sequence in context: A157564 A122182 A276701 * A111316 A297530 A222010

Adjacent sequences:  A157593 A157594 A157595 * A157597 A157598 A157599

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 02 2009

STATUS

approved

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Last modified July 8 05:33 EDT 2020. Contains 335513 sequences. (Running on oeis4.)