A198391 - cp's OEIS frontend

A198391 Numbers m such that Sum_{i=1..k} (1-1/p_i) + Product_{i=1..k} (1-1/p_i) is an integer, where p_i are the k prime factors of m (with multiplicity).

n	a(n)
1	2
2	15
3	20
4	272
5	476
6	19024
7	47425
8	65792
9	125172
10	216900
11	539280
12	1222976
13	1372736
14	2770496
15	3494336
16	5321808
17	5844528
18	6177168
19	7032528
20	8885808
21	20670768
22	60727876
23	69081344
24	82724356
25	95579136
26	544382208
27	907440192
28	1657497600
29	4295032832
30	5048574976

[2, 15, 20, 272, 476, 19024, 47425, 65792, 125172, 216900, 539280, 1222976, 1372736, 2770496, 3494336, 5321808, 5844528, 6177168, 7032528, 8885808, 20670768, 60727876, 69081344, 82724356, 95579136, 544382208, 907440192, 1657497600, 4295032832, 5048574976]

cp's OEIS Frontend

A198391 Numbers m such that Sum_{i=1..k} (1-1/p_i) + Product_{i=1..k} (1-1/p_i) is an integer, where p_i are the k prime factors of m (with multiplicity).

Table of values

List of values