A071342 a(n) = the maximum number of lattice points touched by an origin-centered sphere with radius <= n.

6, 12, 30, 48, 48, 72, 96, 96, 120, 144, 168, 168, 192, 240, 240, 240, 264, 312, 336, 336, 336, 384, 384, 384, 408, 432, 480, 480, 504, 528, 552, 552, 552, 672, 672, 696, 720, 720, 720, 720, 768, 768, 816, 864, 864, 864, 936, 936, 936, 936, 936, 1008, 1008

Offset: 1

Author

Hugo Pfoertner, May 22 2002

Keywords

• easy
• nonn

Examples

			a(4 to 5)=48 because the sphere with radius sqrt(14) touches 48 lattice points; but no sphere touches more, until the radius is sqrt(26).
		

Crossrefs

Cf. A005875, A071339-A071347.

Programs

FORTRAN

See A071339.

Formula

a(n) = max(i=0 to n^2) A005875(i)

Extensions

Edited by Don Reble, Nov 06 2005