A085520 - cp's OEIS frontend

A085520 Numbers whose digits alternate between prime and nonprime.

n	a(n)
1	12
2	13
3	15
4	17
5	20
6	21
7	24
8	26
9	28
10	29
11	30
12	31
13	34
14	36
15	38
16	39
17	42
18	43
19	45
20	47
21	50
22	51
23	54
24	56
25	58
26	59
27	62
28	63
29	65
30	67
31	70
32	71
33	74
34	76
35	78
36	79
37	82
38	83
39	85
40	87
41	92
42	93
43	95
44	97
45	120
46	121
47	124
48	126
49	128
50	129
51	130
52	131
53	134
54	136
55	138
56	139

[12, 13, 15, 17, 20, 21, 24, 26, 28, 29, 30, 31, 34, 36, 38, 39, 42, 43, 45, 47, 50, 51, 54, 56, 58, 59, 62, 63, 65, 67, 70, 71, 74, 76, 78, 79, 82, 83, 85, 87, 92, 93, 95, 97, 120, 121, 124, 126, 128, 129, 130, 131, 134, 136, 138, 139]

cp's OEIS Frontend

A085520 Numbers whose digits alternate between prime and nonprime.

Table of values

List of values

n	a(n)
1	12
2	13
3	15
4	17
5	20
6	21
7	24
8	26
9	28
10	29
11	30
12	31
13	34
14	36
15	38
16	39
17	42
18	43
19	45
20	47
21	50
22	51
23	54
24	56
25	58
26	59
27	62
28	63
29	65
30	67
31	70
32	71
33	74
34	76
35	78
36	79
37	82
38	83
39	85
40	87
41	92
42	93
43	95
44	97
45	120
46	121
47	124
48	126
49	128
50	129
51	130
52	131
53	134
54	136
55	138
56	139

n	a(n)
1	12
2	13
3	15
4	17
5	20
6	21
7	24
8	26
9	28
10	29
11	30
12	31
13	34
14	36
15	38
16	39
17	42
18	43
19	45
20	47
21	50
22	51
23	54
24	56
25	58
26	59
27	62
28	63
29	65
30	67
31	70
32	71
33	74
34	76
35	78
36	79
37	82
38	83
39	85
40	87
41	92
42	93
43	95
44	97
45	120
46	121
47	124
48	126
49	128
50	129
51	130
52	131
53	134
54	136
55	138
56	139

n	a(n)
1	12
2	13
3	15
4	17
5	20
6	21
7	24
8	26
9	28
10	29
11	30
12	31
13	34
14	36
15	38
16	39
17	42
18	43
19	45
20	47
21	50
22	51
23	54
24	56
25	58
26	59
27	62
28	63
29	65
30	67
31	70
32	71
33	74
34	76
35	78
36	79
37	82
38	83
39	85
40	87
41	92
42	93
43	95
44	97
45	120
46	121
47	124
48	126
49	128
50	129
51	130
52	131
53	134
54	136
55	138
56	139