A095385 - cp's OEIS frontend

A095385 Numbers k with property that k is a peak value in 3x+1 trajectory such that both k+1 and k-1 are prime numbers.

n	a(n)
1	4
2	72
3	180
4	192
5	228
6	240
7	312
8	600
9	1092
10	1152
11	1428
12	1488
13	1608
14	1620
15	1872
16	2088
17	2112
18	2592
19	2688
20	3000
21	3168
22	3252
23	3360
24	3528
25	4272
26	4548
27	4800
28	5640
29	6552
30	6960
31	7488
32	7560
33	8088
34	8292
35	8388
36	8820
37	9000
38	9012
39	9240
40	9768
41	10008
42	10068
43	10272

[4, 72, 180, 192, 228, 240, 312, 600, 1092, 1152, 1428, 1488, 1608, 1620, 1872, 2088, 2112, 2592, 2688, 3000, 3168, 3252, 3360, 3528, 4272, 4548, 4800, 5640, 6552, 6960, 7488, 7560, 8088, 8292, 8388, 8820, 9000, 9012, 9240, 9768, 10008, 10068, 10272]

cp's OEIS Frontend

A095385 Numbers k with property that k is a peak value in 3x+1 trajectory such that both k+1 and k-1 are prime numbers.

Table of values

List of values