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A157586 Half the number of length n integer sequences with sum zero and sum of squares 5832. 1
1, 3, 162, 16410, 1839645, 210928977, 17676193171, 1148671947972, 71262995700540, 4352863891098140, 258238261126722129, 14806140740844716211, 815211282605034375060, 42951699550186642926270, 2166061193994862365099390 (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,0,5832)/2.

CROSSREFS

Sequence in context: A173128 A157440 A157559 * A341224 A042439 A212845

Adjacent sequences:  A157583 A157584 A157585 * A157587 A157588 A157589

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 02 2009

STATUS

approved

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Last modified June 26 08:11 EDT 2022. Contains 354877 sequences. (Running on oeis4.)