A359113 - cp's OEIS frontend

A359113 a(n) counts the bases b in the interval 2 to p = prime(n), where p if written in base b gives again a prime number in base b if all digits are written in reverse order.

n	a(n)
1	0
2	1
3	3
4	5
5	7
6	10
7	12
8	9
9	14
10	15
11	20
12	19
13	23
14	26
15	24
16	33
17	22
18	30
19	38
20	36
21	40
22	39
23	38
24	33
25	54
26	49
27	43
28	52
29	37
30	60
31	65
32	53
33	59
34	57
35	50
36	52
37	85
38	52
39	79
40	76
41	57
42	77
43	69
44	103
45	90
46	83
47	84
48	106
49	80
50	68
51	90
52	85
53	89
54	94
55	75
56	100
57	108
58	87
59	128
60	97
61	119
62	99
63	118
64	139
65	105
66	96

[0, 1, 3, 5, 7, 10, 12, 9, 14, 15, 20, 19, 23, 26, 24, 33, 22, 30, 38, 36, 40, 39, 38, 33, 54, 49, 43, 52, 37, 60, 65, 53, 59, 57, 50, 52, 85, 52, 79, 76, 57, 77, 69, 103, 90, 83, 84, 106, 80, 68, 90, 85, 89, 94, 75, 100, 108, 87, 128, 97, 119, 99, 118, 139, 105, 96]

cp's OEIS Frontend

A359113 a(n) counts the bases b in the interval 2 to p = prime(n), where p if written in base b gives again a prime number in base b if all digits are written in reverse order.

Table of values

List of values

n	a(n)
1	0
2	1
3	3
4	5
5	7
6	10
7	12
8	9
9	14
10	15
11	20
12	19
13	23
14	26
15	24
16	33
17	22
18	30
19	38
20	36
21	40
22	39
23	38
24	33
25	54
26	49
27	43
28	52
29	37
30	60
31	65
32	53
33	59
34	57
35	50
36	52
37	85
38	52
39	79
40	76
41	57
42	77
43	69
44	103
45	90
46	83
47	84
48	106
49	80
50	68
51	90
52	85
53	89
54	94
55	75
56	100
57	108
58	87
59	128
60	97
61	119
62	99
63	118
64	139
65	105
66	96

n	a(n)
1	0
2	1
3	3
4	5
5	7
6	10
7	12
8	9
9	14
10	15
11	20
12	19
13	23
14	26
15	24
16	33
17	22
18	30
19	38
20	36
21	40
22	39
23	38
24	33
25	54
26	49
27	43
28	52
29	37
30	60
31	65
32	53
33	59
34	57
35	50
36	52
37	85
38	52
39	79
40	76
41	57
42	77
43	69
44	103
45	90
46	83
47	84
48	106
49	80
50	68
51	90
52	85
53	89
54	94
55	75
56	100
57	108
58	87
59	128
60	97
61	119
62	99
63	118
64	139
65	105
66	96

n	a(n)
1	0
2	1
3	3
4	5
5	7
6	10
7	12
8	9
9	14
10	15
11	20
12	19
13	23
14	26
15	24
16	33
17	22
18	30
19	38
20	36
21	40
22	39
23	38
24	33
25	54
26	49
27	43
28	52
29	37
30	60
31	65
32	53
33	59
34	57
35	50
36	52
37	85
38	52
39	79
40	76
41	57
42	77
43	69
44	103
45	90
46	83
47	84
48	106
49	80
50	68
51	90
52	85
53	89
54	94
55	75
56	100
57	108
58	87
59	128
60	97
61	119
62	99
63	118
64	139
65	105
66	96