A162694 Strictly positive numbers n such that 36*n/(36+n) are integers.

12, 18, 36, 45, 72, 108, 126, 180, 288, 396, 612, 1260

Offset: 1

Author

Vladimir Joseph Stephan Orlovsky, Jul 10 2009

Keywords

• nonn
• fini
• full

Comments

The 36th row of A127730.

The ansatz 36*n/(36+n) = j (any integer j) yields n = 36*j/(36-j) which demonstrates that the sequence is finite if n >= 0. - R. J. Mathar, Jul 13 2009

Positive integers n such that half of the harmonic mean of 36 and n is an integer. - Wesley Ivan Hurt, Sep 07 2014

Crossrefs

Cf. A162688, A162689, A162690, A162691, A162692, A162693

Cf. A127730. [From Franklin T. Adams-Watters, Aug 07 2009]

Programs

Mathematica

Select[Range[1000], IntegerQ[36#/(36 + #)] &] (* Alonso del Arte, Sep 06 2014 *)

Extensions

Edited by R. J. Mathar, Jul 13 2009