A075847 Difference between n^2 and the largest cube <= n^2.

0, 0, 3, 1, 8, 17, 9, 22, 0, 17, 36, 57, 19, 44, 71, 9, 40, 73, 108, 18, 57, 98, 141, 17, 64, 113, 164, 0, 55, 112, 171, 232, 24, 89, 156, 225, 296, 38, 113, 190, 269, 350, 36, 121, 208, 297, 388, 12, 107, 204, 303, 404, 507, 65, 172, 281, 392, 505, 620, 106, 225, 346

Offset: 0

Author

Zak Seidov and Reinhard Zumkeller, Oct 15 2002

Keywords

• easy
• nonn

Comments

a(n) = n^2 - A077106(n).

a(n) = 0 iff n = m^(6*k).

a(n) = 0 when n is a cube. See A070923.

Examples

			a(4)=8 because 4^2 - 2^3 = 8; a(9)=17 because 9^2 - 4^3 = 17.
A077106(20) = 343 = 7^3 is the largest cube <= 20^2 = 400, therefore a(20) = 400 - 343 = 57.
		

Links

• Zak Seidov, Table of n, a(n) for n = 0..2000

Crossrefs

Cf. A000290, A070923, A077110, A077111, A077116.

Cf. A070923.

Programs

Mathematica

Table[a = n^2; a - Floor[a^(1/3)]^3, {n, 0, 300}] (* Vladimir Joseph Stephan Orlovsky, Jun 03 2011 *)

Extensions

Edited by N. J. A. Sloane at the suggestion of Zak Seidov, Oct 30 2008