A258372 - cp's OEIS frontend

A258372 Smallest nonnegative number k not starting or ending with the digit 1 that forms a prime when it is sandwiched between n ones to the left of k and n ones to the right of k.

n	a(n)
1	0
2	3
3	4
4	8
5	36
6	8
7	5
8	72
9	28
10	6
11	79
12	212
13	23
14	6
15	73
16	24
17	52
18	62
19	3
20	28
21	220
22	53
23	75
24	58
25	228
26	9
27	265
28	89
29	214
30	86
31	215
32	4
33	7
34	39
35	295
36	40
37	87
38	216
39	97
40	6
41	264
42	53
43	287
44	223
45	4
46	239
47	259
48	25
49	57
50	364
51	49
52	38
53	93
54	86
55	27
56	30
57	80
58	24
59	6
60	356
61	50
62	645
63	395
64	206

[0, 3, 4, 8, 36, 8, 5, 72, 28, 6, 79, 212, 23, 6, 73, 24, 52, 62, 3, 28, 220, 53, 75, 58, 228, 9, 265, 89, 214, 86, 215, 4, 7, 39, 295, 40, 87, 216, 97, 6, 264, 53, 287, 223, 4, 239, 259, 25, 57, 364, 49, 38, 93, 86, 27, 30, 80, 24, 6, 356, 50, 645, 395, 206]

cp's OEIS Frontend

A258372 Smallest nonnegative number k not starting or ending with the digit 1 that forms a prime when it is sandwiched between n ones to the left of k and n ones to the right of k.

Table of values

List of values

n	a(n)
1	0
2	3
3	4
4	8
5	36
6	8
7	5
8	72
9	28
10	6
11	79
12	212
13	23
14	6
15	73
16	24
17	52
18	62
19	3
20	28
21	220
22	53
23	75
24	58
25	228
26	9
27	265
28	89
29	214
30	86
31	215
32	4
33	7
34	39
35	295
36	40
37	87
38	216
39	97
40	6
41	264
42	53
43	287
44	223
45	4
46	239
47	259
48	25
49	57
50	364
51	49
52	38
53	93
54	86
55	27
56	30
57	80
58	24
59	6
60	356
61	50
62	645
63	395
64	206

n	a(n)
1	0
2	3
3	4
4	8
5	36
6	8
7	5
8	72
9	28
10	6
11	79
12	212
13	23
14	6
15	73
16	24
17	52
18	62
19	3
20	28
21	220
22	53
23	75
24	58
25	228
26	9
27	265
28	89
29	214
30	86
31	215
32	4
33	7
34	39
35	295
36	40
37	87
38	216
39	97
40	6
41	264
42	53
43	287
44	223
45	4
46	239
47	259
48	25
49	57
50	364
51	49
52	38
53	93
54	86
55	27
56	30
57	80
58	24
59	6
60	356
61	50
62	645
63	395
64	206

n	a(n)
1	0
2	3
3	4
4	8
5	36
6	8
7	5
8	72
9	28
10	6
11	79
12	212
13	23
14	6
15	73
16	24
17	52
18	62
19	3
20	28
21	220
22	53
23	75
24	58
25	228
26	9
27	265
28	89
29	214
30	86
31	215
32	4
33	7
34	39
35	295
36	40
37	87
38	216
39	97
40	6
41	264
42	53
43	287
44	223
45	4
46	239
47	259
48	25
49	57
50	364
51	49
52	38
53	93
54	86
55	27
56	30
57	80
58	24
59	6
60	356
61	50
62	645
63	395
64	206