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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A133103 Number of partitions of n^3 into n nonzero squares. 3
1, 1, 2, 1, 10, 34, 156, 734, 3599, 18956, 99893, 548373, 3078558, 17510598, 101960454, 599522778, 3565904170, 21438347021, 129905092421, 794292345434, 4890875249113, 30326545789640, 189195772457341, 1187032920371427 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Robert Gerbicz, May 09 2008, Table of n, a(n) for n = 1..40

EXAMPLE

a(2)=1 because the only way to express 2^3 = 8 as a sum of two squares is 8 = 2^2 + 2^2.

a(3)=2 because 3^3 = 27 = 1^2 + 1^2 + 5^2 = 3^2 + 3^2 + 3^2.

PROG

(PARI) a(i, n, k)=local(s, j); if(k==1, if(issquare(n), return(1), return(0)), s=0; for(j=ceil(sqrt(n/k)), min(i, floor(sqrt(n-k+1))), s+=a(j, n-j^2, k-1)); return(s)) for(n=1, 50, m=n^3; k=n; print1(a(m, m, k)", ") ) \\ Herman Jamke (hermanjamke(AT)fastmail.fm), Dec 16 2007

CROSSREFS

Cf. A000161, A000378, A000141, A005875, A000118, A000132, A008451.

Cf. A133102 (number of ways to express n^3 as a sum of n distinct nonzero squares), A133104 (number of ways to express n^4 as a sum of n nonzero squares).

Sequence in context: A026057 A309234 A071926 * A304359 A054781 A213421

Adjacent sequences:  A133100 A133101 A133102 * A133104 A133105 A133106

KEYWORD

nonn

AUTHOR

Hugo Pfoertner, Sep 11 2007

EXTENSIONS

2 more terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Dec 16 2007

More terms from Robert Gerbicz, May 09 2008

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
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified July 19 22:14 EDT 2019. Contains 325168 sequences. (Running on oeis4.)