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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A071611 Number of points (i,j,k) on the surface of a sphere around (0,0,0) with squared radius A071609(n). 3
6, 12, 24, 30, 48, 72, 96, 120, 144, 168, 192, 240, 264, 312, 336, 384, 408, 432, 480, 504, 528, 552, 576, 600, 672, 696, 720, 768, 816, 864, 936, 1008, 1032, 1056, 1104, 1200, 1248, 1296, 1344, 1440, 1512, 1584, 1680, 1704, 1752, 1848, 1920, 2016 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(n) = number of lattice point on sphere around (0,0,0) with r^2=A071609(n).

LINKS

Hugo Pfoertner, Table of n, a(n) for n = 1..189

EXAMPLE

A sphere with radius 1 has 6 lattice points on its surface, so a(1)=6. A sphere with r=sqrt(2) passes through 12 lattice points of the shape (1,1,0), so a(2)=12. A sphere with r=sqrt(5) passes through 24 lattice points with shape (2,1,0), so a(3)=24. A sphere with r=sqrt(9) passes through 6 lattice points of shape (3,0,0) and through 24 lattice points of shape (2,2,1), so a(4)=6+24=30.

CROSSREFS

Cf. A071342-A071344, A071609, A071610.

Sequence in context: A119840 A298033 A069171 * A216453 A119500 A260633

Adjacent sequences:  A071608 A071609 A071610 * A071612 A071613 A071614

KEYWORD

nonn

AUTHOR

Hugo Pfoertner, May 25 2002

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 October 20 20:24 EDT 2019. Contains 328273 sequences. (Running on oeis4.)