A330816 - cp's OEIS frontend

A330816 Numbers that reach 1 under the iterations of the map k -> k/d(k) if d(k) | k, and k -> k otherwise, where d(k) is the number of divisors of k (A000005).

n	a(n)
1	1
2	2
3	8
4	12
5	80
6	96
7	240
8	2240
9	3600
10	4032
11	20160
12	215040
13	268800
14	387072
15	435456
16	725760
17	6350400
18	77414400
19	94058496
20	97542144
21	139345920
22	162570240
23	278691840
24	365783040
25	452874240
26	457228800
27	5486745600
28	61931520000

[1, 2, 8, 12, 80, 96, 240, 2240, 3600, 4032, 20160, 215040, 268800, 387072, 435456, 725760, 6350400, 77414400, 94058496, 97542144, 139345920, 162570240, 278691840, 365783040, 452874240, 457228800, 5486745600, 61931520000]

cp's OEIS Frontend

A330816 Numbers that reach 1 under the iterations of the map k -> k/d(k) if d(k) | k, and k -> k otherwise, where d(k) is the number of divisors of k (A000005).

Table of values

List of values