A071611 Number of points (i,j,k) on the surface of a sphere around (0,0,0) with squared radius A071609(n).

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

Offset

1,1

Comments

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

Links

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

Formula

a(n) = A005875(A071609(n)). - Daniel Suteu, Aug 13 2021

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. A005875, A071342-A071344, A071609, A071610.

Sequence in context: A358507 A358526 A069171 * A216453 A119500 A260633

Adjacent sequences: A071608 A071609 A071610 * A071612 A071613 A071614

Keyword

nonn

Author

Hugo Pfoertner, May 25 2002

Status

approved