login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A157570 Half the number of length n integer sequences with sum zero and sum of squares 2888. 1
1, 9, 114, 11430, 928665, 57312801, 2929653363, 133959064275, 6012597282660, 258520740868390, 10793900036914731, 439085564014381089, 17106142080255638592, 634240156516816014270, 22487281301691416873070 (list; graph; refs; listen; history; text; internal format)
OFFSET
2,2
LINKS
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,0,2888)/2.
CROSSREFS
Sequence in context: A362576 A356240 A157551 * A223499 A362774 A157233
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 | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 15 15:27 EDT 2024. Contains 371692 sequences. (Running on oeis4.)