A083998 - cp's OEIS frontend

A083998 a(1) = 3; then numbers such that the concatenation a(n)a(n-1)...a(2)a(1)a(2)...a(n-1)a(n) is a prime.

n	a(n)
1	3
2	1
3	1
4	23
5	21
6	3
7	67
8	17
9	3
10	39
11	19
12	33
13	21
14	39
15	77
16	121
17	207
18	9
19	9
20	93
21	53
22	1
23	57
24	93
25	41
26	339
27	9
28	57
29	63
30	1
31	1091
32	273
33	199
34	83
35	213
36	529
37	569
38	397
39	21
40	71
41	481
42	243
43	111
44	419
45	273
46	231
47	63
48	277
49	483
50	201
51	531
52	77
53	139
54	1313
55	529
56	1443
57	587
58	649
59	351
60	273
61	189

[3, 1, 1, 23, 21, 3, 67, 17, 3, 39, 19, 33, 21, 39, 77, 121, 207, 9, 9, 93, 53, 1, 57, 93, 41, 339, 9, 57, 63, 1, 1091, 273, 199, 83, 213, 529, 569, 397, 21, 71, 481, 243, 111, 419, 273, 231, 63, 277, 483, 201, 531, 77, 139, 1313, 529, 1443, 587, 649, 351, 273, 189]

cp's OEIS Frontend

A083998 a(1) = 3; then numbers such that the concatenation a(n)a(n-1)...a(2)a(1)a(2)...a(n-1)a(n) is a prime.

Table of values

List of values