A217560 - cp's OEIS frontend

A217560 Terms as well as digits have alternating primality; this is the lexicographically earliest injective sequence with this property.

n	a(n)
1	1
2	2
3	4
4	3
5	6
6	5
7	8
8	7
9	9
10	29
11	20
12	31
13	21
14	59
15	24
16	71
17	26
18	79
19	28
20	263
21	12
22	13
23	15
24	17
25	42
26	43
27	45
28	47
29	62
30	67
31	63
32	83
33	65
34	97
35	82
36	131
37	30
38	283
39	85
40	139
41	34
42	293
43	87
44	151
45	36
46	307
47	92
48	179
49	38
50	313
51	93
52	421
53	39
54	317
55	95
56	431
57	50
58	347
59	120
60	367
61	121
62	383
63	124
64	397
65	126
66	503
67	128
68	547
69	129
70	563
71	130
72	587
73	134
74	593
75	136
76	743
77	138
78	787

[1, 2, 4, 3, 6, 5, 8, 7, 9, 29, 20, 31, 21, 59, 24, 71, 26, 79, 28, 263, 12, 13, 15, 17, 42, 43, 45, 47, 62, 67, 63, 83, 65, 97, 82, 131, 30, 283, 85, 139, 34, 293, 87, 151, 36, 307, 92, 179, 38, 313, 93, 421, 39, 317, 95, 431, 50, 347, 120, 367, 121, 383, 124, 397, 126, 503, 128, 547, 129, 563, 130, 587, 134, 593, 136, 743, 138, 787]

cp's OEIS Frontend

A217560 Terms as well as digits have alternating primality; this is the lexicographically earliest injective sequence with this property.

Table of values

List of values

n	a(n)
1	1
2	2
3	4
4	3
5	6
6	5
7	8
8	7
9	9
10	29
11	20
12	31
13	21
14	59
15	24
16	71
17	26
18	79
19	28
20	263
21	12
22	13
23	15
24	17
25	42
26	43
27	45
28	47
29	62
30	67
31	63
32	83
33	65
34	97
35	82
36	131
37	30
38	283
39	85
40	139
41	34
42	293
43	87
44	151
45	36
46	307
47	92
48	179
49	38
50	313
51	93
52	421
53	39
54	317
55	95
56	431
57	50
58	347
59	120
60	367
61	121
62	383
63	124
64	397
65	126
66	503
67	128
68	547
69	129
70	563
71	130
72	587
73	134
74	593
75	136
76	743
77	138
78	787

n	a(n)
1	1
2	2
3	4
4	3
5	6
6	5
7	8
8	7
9	9
10	29
11	20
12	31
13	21
14	59
15	24
16	71
17	26
18	79
19	28
20	263
21	12
22	13
23	15
24	17
25	42
26	43
27	45
28	47
29	62
30	67
31	63
32	83
33	65
34	97
35	82
36	131
37	30
38	283
39	85
40	139
41	34
42	293
43	87
44	151
45	36
46	307
47	92
48	179
49	38
50	313
51	93
52	421
53	39
54	317
55	95
56	431
57	50
58	347
59	120
60	367
61	121
62	383
63	124
64	397
65	126
66	503
67	128
68	547
69	129
70	563
71	130
72	587
73	134
74	593
75	136
76	743
77	138
78	787

n	a(n)
1	1
2	2
3	4
4	3
5	6
6	5
7	8
8	7
9	9
10	29
11	20
12	31
13	21
14	59
15	24
16	71
17	26
18	79
19	28
20	263
21	12
22	13
23	15
24	17
25	42
26	43
27	45
28	47
29	62
30	67
31	63
32	83
33	65
34	97
35	82
36	131
37	30
38	283
39	85
40	139
41	34
42	293
43	87
44	151
45	36
46	307
47	92
48	179
49	38
50	313
51	93
52	421
53	39
54	317
55	95
56	431
57	50
58	347
59	120
60	367
61	121
62	383
63	124
64	397
65	126
66	503
67	128
68	547
69	129
70	563
71	130
72	587
73	134
74	593
75	136
76	743
77	138
78	787