A359243 - cp's OEIS frontend

A359243 a(1) = 1, a(2) = 2; let j = a(n-1); for n > 2, if j is prime then a(n) = least novel k such that phi(k)/k < phi(j)/j, else a(n) = least novel k such that phi(k)/k > phi(j)/j, where phi(x) = A000010(x).

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

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

cp's OEIS Frontend

A359243 a(1) = 1, a(2) = 2; let j = a(n-1); for n > 2, if j is prime then a(n) = least novel k such that phi(k)/k < phi(j)/j, else a(n) = least novel k such that phi(k)/k > phi(j)/j, where phi(x) = A000010(x).

Table of values

List of values

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

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

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