A334814 - cp's OEIS frontend

A334814 Least number that reaches 1 after n iterations of the map k -> sigma(k)/d(k) if d(k) | sigma(k), and k -> 1 otherwise, where d(k) is the number of divisors of k (A000005) and sigma(k) is their sum (A000203).

n	a(n)
0	1
1	2
2	3
3	5
4	11
5	29
6	107
7	257
8	941
9	2017
10	11261
11	45039
12	441073
13	2151073
14	8575873
15	42884161
16	220268161
17	440536321

[1, 2, 3, 5, 11, 29, 107, 257, 941, 2017, 11261, 45039, 441073, 2151073, 8575873, 42884161, 220268161, 440536321]