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A157555 Half the number of length n integer sequences with sum zero and sum of squares 1058. 1
1, 3, 150, 5070, 182175, 5887791, 180232444, 5773910724, 178835952285, 4946264437455, 125256800641170, 2987737855296558, 68285219070825029, 1509200139206357640, 32387266774022554680, 675011623200542959496 (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,0,1058)/2.

CROSSREFS

Sequence in context: A181748 A118840 A111816 * A157578 A137802 A100203

Adjacent sequences:  A157552 A157553 A157554 * A157556 A157557 A157558

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 02 2009

STATUS

approved

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Last modified December 6 11:48 EST 2021. Contains 349563 sequences. (Running on oeis4.)