A138561 - cp's OEIS frontend

A138561 Start with the list {1}; for each n >= 1, append p(n) primes followed by c(n) composite numbers, where p(n) is the n-th prime and c(n) is the n-th composite number.

n	a(n)
1	1
2	2
3	3
4	4
5	6
6	8
7	9
8	5
9	7
10	11
11	10
12	12
13	14
14	15
15	16
16	18
17	13
18	17
19	19
20	23
21	29
22	20
23	21
24	22
25	24
26	25
27	26
28	27
29	28
30	31
31	37
32	41
33	43
34	47
35	53
36	59
37	30
38	32
39	33
40	34
41	35
42	36
43	38
44	39
45	40
46	61
47	67
48	71
49	73
50	79
51	83
52	89
53	97
54	101
55	103
56	107
57	42
58	44
59	45
60	46
61	48
62	49
63	50
64	51
65	52
66	54
67	109
68	113
69	127
70	131

[1, 2, 3, 4, 6, 8, 9, 5, 7, 11, 10, 12, 14, 15, 16, 18, 13, 17, 19, 23, 29, 20, 21, 22, 24, 25, 26, 27, 28, 31, 37, 41, 43, 47, 53, 59, 30, 32, 33, 34, 35, 36, 38, 39, 40, 61, 67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 42, 44, 45, 46, 48, 49, 50, 51, 52, 54, 109, 113, 127, 131]

cp's OEIS Frontend

A138561 Start with the list {1}; for each n >= 1, append p(n) primes followed by c(n) composite numbers, where p(n) is the n-th prime and c(n) is the n-th composite number.

Table of values

List of values

n	a(n)
1	1
2	2
3	3
4	4
5	6
6	8
7	9
8	5
9	7
10	11
11	10
12	12
13	14
14	15
15	16
16	18
17	13
18	17
19	19
20	23
21	29
22	20
23	21
24	22
25	24
26	25
27	26
28	27
29	28
30	31
31	37
32	41
33	43
34	47
35	53
36	59
37	30
38	32
39	33
40	34
41	35
42	36
43	38
44	39
45	40
46	61
47	67
48	71
49	73
50	79
51	83
52	89
53	97
54	101
55	103
56	107
57	42
58	44
59	45
60	46
61	48
62	49
63	50
64	51
65	52
66	54
67	109
68	113
69	127
70	131

n	a(n)
1	1
2	2
3	3
4	4
5	6
6	8
7	9
8	5
9	7
10	11
11	10
12	12
13	14
14	15
15	16
16	18
17	13
18	17
19	19
20	23
21	29
22	20
23	21
24	22
25	24
26	25
27	26
28	27
29	28
30	31
31	37
32	41
33	43
34	47
35	53
36	59
37	30
38	32
39	33
40	34
41	35
42	36
43	38
44	39
45	40
46	61
47	67
48	71
49	73
50	79
51	83
52	89
53	97
54	101
55	103
56	107
57	42
58	44
59	45
60	46
61	48
62	49
63	50
64	51
65	52
66	54
67	109
68	113
69	127
70	131

n	a(n)
1	1
2	2
3	3
4	4
5	6
6	8
7	9
8	5
9	7
10	11
11	10
12	12
13	14
14	15
15	16
16	18
17	13
18	17
19	19
20	23
21	29
22	20
23	21
24	22
25	24
26	25
27	26
28	27
29	28
30	31
31	37
32	41
33	43
34	47
35	53
36	59
37	30
38	32
39	33
40	34
41	35
42	36
43	38
44	39
45	40
46	61
47	67
48	71
49	73
50	79
51	83
52	89
53	97
54	101
55	103
56	107
57	42
58	44
59	45
60	46
61	48
62	49
63	50
64	51
65	52
66	54
67	109
68	113
69	127
70	131