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A157600 Half the number of length n integer sequences with sum zero and sum of squares 9248. 1
1, 3, 102, 30030, 5399445, 596031513, 53828636911, 4407428497293, 353304900193680, 27176309595536035, 2030727740280136689, 147839184902264090742, 10306962174706523122706, 683847390057269455279395 (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,0,9248)/2.

CROSSREFS

Sequence in context: A224817 A157549 A157566 * A139908 A128070 A323036

Adjacent sequences:  A157597 A157598 A157599 * A157601 A157602 A157603

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 02 2009

STATUS

approved

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Last modified May 21 00:36 EDT 2022. Contains 353886 sequences. (Running on oeis4.)