login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A157597 Half the number of length n integer sequences with sum zero and sum of squares 8450. 2
1, 9, 630, 48670, 4293525, 358348053, 32224041500, 2966406894648, 259556693304825, 20157653282906667, 1439903350550159550, 97064374251531230622, 6271845201623139087495, 391742584864070048279685 (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,0,8450)/2.

CROSSREFS

Sequence in context: A188423 A158881 A188394 * A211611 A280904 A210053

Adjacent sequences:  A157594 A157595 A157596 * A157598 A157599 A157600

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 02 2009

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy .

Last modified February 18 20:32 EST 2018. Contains 299330 sequences. (Running on oeis4.)