A286095 - cp's OEIS frontend

A286095 Composite numbers n such that tau(n) (number of divisors of n) is prime and sigma(n) (sum of divisors of n) is not prime.

n	a(n)
1	49
2	81
3	121
4	169
5	361
6	529
7	625
8	841
9	961
10	1024
11	1369
12	1849
13	2209
14	2809
15	3721
16	4489
17	5329
18	6241
19	6889
20	9409
21	10609
22	11449
23	11881
24	12769
25	14641
26	16129
27	18769
28	19321
29	22201
30	22801
31	24649
32	26569
33	32041
34	32761
35	36481
36	37249
37	38809
38	39601
39	44521
40	49729
41	51529
42	52441
43	54289

[49, 81, 121, 169, 361, 529, 625, 841, 961, 1024, 1369, 1849, 2209, 2809, 3721, 4489, 5329, 6241, 6889, 9409, 10609, 11449, 11881, 12769, 14641, 16129, 18769, 19321, 22201, 22801, 24649, 26569, 32041, 32761, 36481, 37249, 38809, 39601, 44521, 49729, 51529, 52441, 54289]

cp's OEIS Frontend

A286095 Composite numbers n such that tau(n) (number of divisors of n) is prime and sigma(n) (sum of divisors of n) is not prime.

Table of values

List of values