A128859 - cp's OEIS frontend

A128859 Let p be the n-th odd prime; a(n) is the number of primitive roots of p which are <= (p-1)/2.

n	a(n)
1	0
2	1
3	1
4	1
5	2
6	4
7	2
8	4
9	6
10	4
11	6
12	8
13	6
14	9
15	12
16	10
17	8
18	10
19	9
20	12
21	10
22	16
23	20
24	16
25	20
26	13
27	22
28	18
29	24
30	17
31	18
32	32
33	18
34	36
35	16
36	24
37	26
38	36
39	42
40	37
41	24
42	29
43	32
44	42
45	23
46	16
47	38
48	49
49	36
50	56
51	44
52	32
53	44
54	64
55	59
56	66
57	33
58	44
59	48
60	40
61	72
62	48
63	55
64	48
65	78
66	35
67	48
68	79
69	56
70	80
71	80
72	60
73	60
74	55

[0, 1, 1, 1, 2, 4, 2, 4, 6, 4, 6, 8, 6, 9, 12, 10, 8, 10, 9, 12, 10, 16, 20, 16, 20, 13, 22, 18, 24, 17, 18, 32, 18, 36, 16, 24, 26, 36, 42, 37, 24, 29, 32, 42, 23, 16, 38, 49, 36, 56, 44, 32, 44, 64, 59, 66, 33, 44, 48, 40, 72, 48, 55, 48, 78, 35, 48, 79, 56, 80, 80, 60, 60, 55]

cp's OEIS Frontend

A128859 Let p be the n-th odd prime; a(n) is the number of primitive roots of p which are <= (p-1)/2.

Table of values

List of values

n	a(n)
1	0
2	1
3	1
4	1
5	2
6	4
7	2
8	4
9	6
10	4
11	6
12	8
13	6
14	9
15	12
16	10
17	8
18	10
19	9
20	12
21	10
22	16
23	20
24	16
25	20
26	13
27	22
28	18
29	24
30	17
31	18
32	32
33	18
34	36
35	16
36	24
37	26
38	36
39	42
40	37
41	24
42	29
43	32
44	42
45	23
46	16
47	38
48	49
49	36
50	56
51	44
52	32
53	44
54	64
55	59
56	66
57	33
58	44
59	48
60	40
61	72
62	48
63	55
64	48
65	78
66	35
67	48
68	79
69	56
70	80
71	80
72	60
73	60
74	55

n	a(n)
1	0
2	1
3	1
4	1
5	2
6	4
7	2
8	4
9	6
10	4
11	6
12	8
13	6
14	9
15	12
16	10
17	8
18	10
19	9
20	12
21	10
22	16
23	20
24	16
25	20
26	13
27	22
28	18
29	24
30	17
31	18
32	32
33	18
34	36
35	16
36	24
37	26
38	36
39	42
40	37
41	24
42	29
43	32
44	42
45	23
46	16
47	38
48	49
49	36
50	56
51	44
52	32
53	44
54	64
55	59
56	66
57	33
58	44
59	48
60	40
61	72
62	48
63	55
64	48
65	78
66	35
67	48
68	79
69	56
70	80
71	80
72	60
73	60
74	55

n	a(n)
1	0
2	1
3	1
4	1
5	2
6	4
7	2
8	4
9	6
10	4
11	6
12	8
13	6
14	9
15	12
16	10
17	8
18	10
19	9
20	12
21	10
22	16
23	20
24	16
25	20
26	13
27	22
28	18
29	24
30	17
31	18
32	32
33	18
34	36
35	16
36	24
37	26
38	36
39	42
40	37
41	24
42	29
43	32
44	42
45	23
46	16
47	38
48	49
49	36
50	56
51	44
52	32
53	44
54	64
55	59
56	66
57	33
58	44
59	48
60	40
61	72
62	48
63	55
64	48
65	78
66	35
67	48
68	79
69	56
70	80
71	80
72	60
73	60
74	55