A237183 - cp's OEIS frontend

A237183 Primes p with phi(p+1) - 1 and phi(p+1) + 1 both prime, where phi(.) is Euler's totient function.

n	a(n)
1	7
2	11
3	13
4	17
5	37
6	41
7	53
8	61
9	97
10	151
11	181
12	197
13	227
14	233
15	251
16	269
17	277
18	397
19	433
20	457
21	487
22	541
23	557
24	571
25	593
26	619
27	631
28	719
29	743
30	769
31	839
32	857
33	929
34	941
35	947
36	953
37	1013
38	1021
39	1049
40	1061
41	1063
42	1201
43	1237
44	1277
45	1307
46	1321
47	1367
48	1481
49	1511
50	1549

[7, 11, 13, 17, 37, 41, 53, 61, 97, 151, 181, 197, 227, 233, 251, 269, 277, 397, 433, 457, 487, 541, 557, 571, 593, 619, 631, 719, 743, 769, 839, 857, 929, 941, 947, 953, 1013, 1021, 1049, 1061, 1063, 1201, 1237, 1277, 1307, 1321, 1367, 1481, 1511, 1549]

cp's OEIS Frontend

A237183 Primes p with phi(p+1) - 1 and phi(p+1) + 1 both prime, where phi(.) is Euler's totient function.

Table of values

List of values