A325339 Number of divisors of n^3 that are <= n.

1, 2, 2, 3, 2, 5, 2, 4, 3, 6, 2, 8, 2, 6, 5, 5, 2, 9, 2, 8, 5, 6, 2, 11, 3, 6, 4, 8, 2, 17, 2, 6, 6, 6, 5, 14, 2, 6, 6, 11, 2, 17, 2, 9, 8, 6, 2, 15, 3, 10, 6, 9, 2, 13, 5, 11, 6, 6, 2, 26, 2, 6, 8, 7, 5, 18, 2, 10, 6, 17, 2, 18, 2, 6, 9, 10, 5, 19, 2, 14, 5

Offset: 1

Author

Clark Kimberling, Apr 21 2019

Keywords

• nonn
• easy

Examples

			a(10) counts these 6 divisors: 1,2,4,5,8,10.
		

Links

• Clark Kimberling, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A000578, A048785.

Programs

Mathematica

Table[Length[Select[Divisors[n^3], # <= n &]], {n, 1, 120}]

PARI

a(n) = sumdiv(n^3, d, d <= n); \\ Michel Marcus, Apr 22 2019