A267970 Conjectured list of positive numbers n such that the Collatz-like map T: if x > 1 and x odd, x -> 5*x+1 and, if x even, x -> x/2, when started at n, never repeats.

7, 9, 11, 14, 18, 21, 22, 23, 25, 28, 29, 31, 35, 36, 37, 39, 41, 42, 44, 45, 46, 47, 49, 50, 53, 55, 56, 57, 58, 59, 61, 62, 63, 67, 69, 70, 71, 72, 73, 74, 75, 77, 78, 79, 81, 82, 84, 85, 87, 88, 89, 90, 91, 92, 93, 94, 95, 98, 99, 100

Offset

1,1

Comments

A companion to A232711 (which conjecturally lists the numbers whose trajectory reaches 1), and A267969 (which conjecturally lists the numbers whose trajectory cycles but does not reach 1). The present sequences conjecturally lists the numbers whose trajectory diverges.

The numbers listed have trajectories that have not cycled in the first 10000 steps. (But this does not mean much. There are quite small numbers that only cycle after 13000 iterations. - N. J. A. Sloane, Jan 23 2016)

Links

Dmitry Kamenetsky, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A232711, A267969.

Sequence in context: A264814 A029612 A120165 * A024828 A139058 A242103

Adjacent sequences: A267967 A267968 A267969 * A267971 A267972 A267973

Keyword

nonn

Author

Michel Lagneau, Jan 19 2016

Extensions

Entry revised by N. J. A. Sloane, Jan 23 2016

a(18)-a(60) from Dmitry Kamenetsky, Jun 26 2024

Status

approved