A175127 a(n) = the largest numbers m with the number of steps n of iterations of {r - (smallest prime divisor of r)} needed to reach 0 starting at r = m .

4, 6, 9, 10, 12, 15, 16, 18, 21, 25, 24, 27, 28, 30, 35, 34, 36, 39, 40, 42, 49, 46, 48, 51, 55, 54, 57, 58, 60, 65, 64, 66, 69, 70, 77, 75, 76, 78, 81, 85, 84, 91, 88, 90, 95, 94, 96, 99, 100, 102, 105, 106, 108, 111, 121, 119, 117, 118, 120, 125, 124, 126, 133, 130, 132

Offset

2,1

Comments

A175126(a(n)) = A175126(A005843(n)) = n. [From Jaroslav Krizek, May 12 2010]

Links

Table of n, a(n) for n=2..66.

Example

Example (a(4)=9): 9-3=6, 6-2=4, 4-2=2, 2-2=0; iterations has 4 steps and number 9 is the largest number with such result.

Crossrefs

Cf. A175126, A046666, A005843.

Sequence in context: A328028 A366318 A339424 * A174166 A171401 A120329

Adjacent sequences: A175124 A175125 A175126 * A175128 A175129 A175130

Keyword

nonn

Author

Jaroslav Krizek, Feb 15 2010

Extensions

Edited by R. J. Mathar, Mar 11 2010

Status

approved