A189977 - cp's OEIS frontend

A189977 Primes p such that d(p+1) = 2*d(p-1), where d(k) counts the divisors of k.

n	a(n)
1	2
2	23
3	149
4	293
5	311
6	439
7	557
8	569
9	743
10	773
11	857
12	1031
13	1151
14	1493
15	1607
16	1663
17	1709
18	1733
19	1879
20	1913
21	2069
22	2141
23	2423
24	2711
25	2719
26	2729
27	2789
28	2969
29	3191
30	3209
31	3559
32	3607
33	3767
34	3821
35	3833
36	3847
37	3929
38	3967
39	4019
40	4073
41	4229
42	4339
43	4451
44	4517
45	4549

[2, 23, 149, 293, 311, 439, 557, 569, 743, 773, 857, 1031, 1151, 1493, 1607, 1663, 1709, 1733, 1879, 1913, 2069, 2141, 2423, 2711, 2719, 2729, 2789, 2969, 3191, 3209, 3559, 3607, 3767, 3821, 3833, 3847, 3929, 3967, 4019, 4073, 4229, 4339, 4451, 4517, 4549]

cp's OEIS Frontend

A189977 Primes p such that d(p+1) = 2*d(p-1), where d(k) counts the divisors of k.

Table of values

List of values