A115316 - cp's OEIS frontend

A115316 Lexicographically earliest permutation of the natural numbers such that each prime number is followed by exactly two composite numbers.

n	a(n)
1	1
2	2
3	4
4	6
5	3
6	8
7	9
8	5
9	10
10	12
11	7
12	14
13	15
14	11
15	16
16	18
17	13
18	20
19	21
20	17
21	22
22	24
23	19
24	25
25	26
26	23
27	27
28	28
29	29
30	30
31	32
32	31
33	33
34	34
35	37
36	35
37	36
38	41
39	38
40	39
41	43
42	40
43	42
44	47
45	44
46	45
47	53
48	46
49	48
50	59
51	49
52	50
53	61
54	51
55	52
56	67
57	54
58	55
59	71
60	56
61	57
62	73
63	58
64	60
65	79
66	62
67	63
68	83
69	64
70	65
71	89
72	66

[1, 2, 4, 6, 3, 8, 9, 5, 10, 12, 7, 14, 15, 11, 16, 18, 13, 20, 21, 17, 22, 24, 19, 25, 26, 23, 27, 28, 29, 30, 32, 31, 33, 34, 37, 35, 36, 41, 38, 39, 43, 40, 42, 47, 44, 45, 53, 46, 48, 59, 49, 50, 61, 51, 52, 67, 54, 55, 71, 56, 57, 73, 58, 60, 79, 62, 63, 83, 64, 65, 89, 66]

cp's OEIS Frontend

A115316 Lexicographically earliest permutation of the natural numbers such that each prime number is followed by exactly two composite numbers.

Table of values

List of values

n	a(n)
1	1
2	2
3	4
4	6
5	3
6	8
7	9
8	5
9	10
10	12
11	7
12	14
13	15
14	11
15	16
16	18
17	13
18	20
19	21
20	17
21	22
22	24
23	19
24	25
25	26
26	23
27	27
28	28
29	29
30	30
31	32
32	31
33	33
34	34
35	37
36	35
37	36
38	41
39	38
40	39
41	43
42	40
43	42
44	47
45	44
46	45
47	53
48	46
49	48
50	59
51	49
52	50
53	61
54	51
55	52
56	67
57	54
58	55
59	71
60	56
61	57
62	73
63	58
64	60
65	79
66	62
67	63
68	83
69	64
70	65
71	89
72	66

n	a(n)
1	1
2	2
3	4
4	6
5	3
6	8
7	9
8	5
9	10
10	12
11	7
12	14
13	15
14	11
15	16
16	18
17	13
18	20
19	21
20	17
21	22
22	24
23	19
24	25
25	26
26	23
27	27
28	28
29	29
30	30
31	32
32	31
33	33
34	34
35	37
36	35
37	36
38	41
39	38
40	39
41	43
42	40
43	42
44	47
45	44
46	45
47	53
48	46
49	48
50	59
51	49
52	50
53	61
54	51
55	52
56	67
57	54
58	55
59	71
60	56
61	57
62	73
63	58
64	60
65	79
66	62
67	63
68	83
69	64
70	65
71	89
72	66

n	a(n)
1	1
2	2
3	4
4	6
5	3
6	8
7	9
8	5
9	10
10	12
11	7
12	14
13	15
14	11
15	16
16	18
17	13
18	20
19	21
20	17
21	22
22	24
23	19
24	25
25	26
26	23
27	27
28	28
29	29
30	30
31	32
32	31
33	33
34	34
35	37
36	35
37	36
38	41
39	38
40	39
41	43
42	40
43	42
44	47
45	44
46	45
47	53
48	46
49	48
50	59
51	49
52	50
53	61
54	51
55	52
56	67
57	54
58	55
59	71
60	56
61	57
62	73
63	58
64	60
65	79
66	62
67	63
68	83
69	64
70	65
71	89
72	66