A227413 - cp's OEIS frontend

A227413 a(1)=1, a(2n)=nthprime(a(n)), a(2n+1)=nthcomposite(a(n)), where nthprime = A000040, nthcomposite = A002808.

n	a(n)
1	1
2	2
3	4
4	3
5	6
6	7
7	9
8	5
9	8
10	13
11	12
12	17
13	14
14	23
15	16
16	11
17	10
18	19
19	15
20	41
21	22
22	37
23	21
24	59
25	27
26	43
27	24
28	83
29	35
30	53
31	26
32	31
33	20
34	29
35	18
36	67
37	30
38	47
39	25
40	179
41	58
42	79
43	34
44	157
45	54
46	73
47	33
48	277
49	82
50	103
51	40
52	191
53	62
54	89
55	36
56	431
57	114
58	149
59	51
60	241
61	75
62	101
63	39
64	127
65	46

[1, 2, 4, 3, 6, 7, 9, 5, 8, 13, 12, 17, 14, 23, 16, 11, 10, 19, 15, 41, 22, 37, 21, 59, 27, 43, 24, 83, 35, 53, 26, 31, 20, 29, 18, 67, 30, 47, 25, 179, 58, 79, 34, 157, 54, 73, 33, 277, 82, 103, 40, 191, 62, 89, 36, 431, 114, 149, 51, 241, 75, 101, 39, 127, 46]

cp's OEIS Frontend

A227413 a(1)=1, a(2n)=nthprime(a(n)), a(2n+1)=nthcomposite(a(n)), where nthprime = A000040, nthcomposite = A002808.

Table of values

List of values

n	a(n)
1	1
2	2
3	4
4	3
5	6
6	7
7	9
8	5
9	8
10	13
11	12
12	17
13	14
14	23
15	16
16	11
17	10
18	19
19	15
20	41
21	22
22	37
23	21
24	59
25	27
26	43
27	24
28	83
29	35
30	53
31	26
32	31
33	20
34	29
35	18
36	67
37	30
38	47
39	25
40	179
41	58
42	79
43	34
44	157
45	54
46	73
47	33
48	277
49	82
50	103
51	40
52	191
53	62
54	89
55	36
56	431
57	114
58	149
59	51
60	241
61	75
62	101
63	39
64	127
65	46

n	a(n)
1	1
2	2
3	4
4	3
5	6
6	7
7	9
8	5
9	8
10	13
11	12
12	17
13	14
14	23
15	16
16	11
17	10
18	19
19	15
20	41
21	22
22	37
23	21
24	59
25	27
26	43
27	24
28	83
29	35
30	53
31	26
32	31
33	20
34	29
35	18
36	67
37	30
38	47
39	25
40	179
41	58
42	79
43	34
44	157
45	54
46	73
47	33
48	277
49	82
50	103
51	40
52	191
53	62
54	89
55	36
56	431
57	114
58	149
59	51
60	241
61	75
62	101
63	39
64	127
65	46

n	a(n)
1	1
2	2
3	4
4	3
5	6
6	7
7	9
8	5
9	8
10	13
11	12
12	17
13	14
14	23
15	16
16	11
17	10
18	19
19	15
20	41
21	22
22	37
23	21
24	59
25	27
26	43
27	24
28	83
29	35
30	53
31	26
32	31
33	20
34	29
35	18
36	67
37	30
38	47
39	25
40	179
41	58
42	79
43	34
44	157
45	54
46	73
47	33
48	277
49	82
50	103
51	40
52	191
53	62
54	89
55	36
56	431
57	114
58	149
59	51
60	241
61	75
62	101
63	39
64	127
65	46