A087606 - cp's OEIS frontend

A087606 Smallest k such that n times concatenation of k with itself followed by a 9 is a prime, or 0 if no such number exists.

n	a(n)
1	1
2	2
3	0
4	1
5	1
6	0
7	1
8	11
9	0
10	64
11	5
12	0
13	2
14	31
15	0
16	1
17	5
18	0
19	10
20	65
21	0
22	41
23	212
24	0
25	5
26	79
27	0
28	41
29	160
30	0
31	5
32	94
33	0
34	8
35	82
36	0
37	23
38	43
39	0
40	40
41	26
42	0
43	391
44	119
45	0
46	212
47	4
48	0
49	1
50	160
51	0
52	134
53	28
54	0
55	208
56	50
57	0
58	248
59	35
60	0
61	113
62	43
63	0
64	79
65	7
66	0
67	70
68	170
69	0
70	64
71	94
72	0
73	19
74	86
75	0
76	10
77	118
78	0
79	34
80	98

[1, 2, 0, 1, 1, 0, 1, 11, 0, 64, 5, 0, 2, 31, 0, 1, 5, 0, 10, 65, 0, 41, 212, 0, 5, 79, 0, 41, 160, 0, 5, 94, 0, 8, 82, 0, 23, 43, 0, 40, 26, 0, 391, 119, 0, 212, 4, 0, 1, 160, 0, 134, 28, 0, 208, 50, 0, 248, 35, 0, 113, 43, 0, 79, 7, 0, 70, 170, 0, 64, 94, 0, 19, 86, 0, 10, 118, 0, 34, 98]

cp's OEIS Frontend

A087606 Smallest k such that n times concatenation of k with itself followed by a 9 is a prime, or 0 if no such number exists.

Table of values

List of values

n	a(n)
1	1
2	2
3	0
4	1
5	1
6	0
7	1
8	11
9	0
10	64
11	5
12	0
13	2
14	31
15	0
16	1
17	5
18	0
19	10
20	65
21	0
22	41
23	212
24	0
25	5
26	79
27	0
28	41
29	160
30	0
31	5
32	94
33	0
34	8
35	82
36	0
37	23
38	43
39	0
40	40
41	26
42	0
43	391
44	119
45	0
46	212
47	4
48	0
49	1
50	160
51	0
52	134
53	28
54	0
55	208
56	50
57	0
58	248
59	35
60	0
61	113
62	43
63	0
64	79
65	7
66	0
67	70
68	170
69	0
70	64
71	94
72	0
73	19
74	86
75	0
76	10
77	118
78	0
79	34
80	98

n	a(n)
1	1
2	2
3	0
4	1
5	1
6	0
7	1
8	11
9	0
10	64
11	5
12	0
13	2
14	31
15	0
16	1
17	5
18	0
19	10
20	65
21	0
22	41
23	212
24	0
25	5
26	79
27	0
28	41
29	160
30	0
31	5
32	94
33	0
34	8
35	82
36	0
37	23
38	43
39	0
40	40
41	26
42	0
43	391
44	119
45	0
46	212
47	4
48	0
49	1
50	160
51	0
52	134
53	28
54	0
55	208
56	50
57	0
58	248
59	35
60	0
61	113
62	43
63	0
64	79
65	7
66	0
67	70
68	170
69	0
70	64
71	94
72	0
73	19
74	86
75	0
76	10
77	118
78	0
79	34
80	98

n	a(n)
1	1
2	2
3	0
4	1
5	1
6	0
7	1
8	11
9	0
10	64
11	5
12	0
13	2
14	31
15	0
16	1
17	5
18	0
19	10
20	65
21	0
22	41
23	212
24	0
25	5
26	79
27	0
28	41
29	160
30	0
31	5
32	94
33	0
34	8
35	82
36	0
37	23
38	43
39	0
40	40
41	26
42	0
43	391
44	119
45	0
46	212
47	4
48	0
49	1
50	160
51	0
52	134
53	28
54	0
55	208
56	50
57	0
58	248
59	35
60	0
61	113
62	43
63	0
64	79
65	7
66	0
67	70
68	170
69	0
70	64
71	94
72	0
73	19
74	86
75	0
76	10
77	118
78	0
79	34
80	98