A016035 - cp's OEIS frontend

A016035 a(n) = Sum_{j|n, 1 < j < n} phi(j). Also a(n) = n - phi(n) - 1 for n > 1.

n	a(n)
1	0
2	0
3	0
4	1
5	0
6	3
7	0
8	3
9	2
10	5
11	0
12	7
13	0
14	7
15	6
16	7
17	0
18	11
19	0
20	11
21	8
22	11
23	0
24	15
25	4
26	13
27	8
28	15
29	0
30	21
31	0
32	15
33	12
34	17
35	10
36	23
37	0
38	19
39	14
40	23
41	0
42	29
43	0
44	23
45	20
46	23
47	0
48	31
49	6
50	29
51	18
52	27
53	0
54	35
55	14
56	31
57	20
58	29
59	0
60	43
61	0
62	31
63	26
64	31
65	16
66	45
67	0
68	35
69	24
70	45
71	0
72	47
73	0
74	37
75	34
76	39
77	16
78	53

[0, 0, 0, 1, 0, 3, 0, 3, 2, 5, 0, 7, 0, 7, 6, 7, 0, 11, 0, 11, 8, 11, 0, 15, 4, 13, 8, 15, 0, 21, 0, 15, 12, 17, 10, 23, 0, 19, 14, 23, 0, 29, 0, 23, 20, 23, 0, 31, 6, 29, 18, 27, 0, 35, 14, 31, 20, 29, 0, 43, 0, 31, 26, 31, 16, 45, 0, 35, 24, 45, 0, 47, 0, 37, 34, 39, 16, 53]

cp's OEIS Frontend

A016035 a(n) = Sum_{j|n, 1 < j < n} phi(j). Also a(n) = n - phi(n) - 1 for n > 1.

Table of values

List of values

n	a(n)
1	0
2	0
3	0
4	1
5	0
6	3
7	0
8	3
9	2
10	5
11	0
12	7
13	0
14	7
15	6
16	7
17	0
18	11
19	0
20	11
21	8
22	11
23	0
24	15
25	4
26	13
27	8
28	15
29	0
30	21
31	0
32	15
33	12
34	17
35	10
36	23
37	0
38	19
39	14
40	23
41	0
42	29
43	0
44	23
45	20
46	23
47	0
48	31
49	6
50	29
51	18
52	27
53	0
54	35
55	14
56	31
57	20
58	29
59	0
60	43
61	0
62	31
63	26
64	31
65	16
66	45
67	0
68	35
69	24
70	45
71	0
72	47
73	0
74	37
75	34
76	39
77	16
78	53

n	a(n)
1	0
2	0
3	0
4	1
5	0
6	3
7	0
8	3
9	2
10	5
11	0
12	7
13	0
14	7
15	6
16	7
17	0
18	11
19	0
20	11
21	8
22	11
23	0
24	15
25	4
26	13
27	8
28	15
29	0
30	21
31	0
32	15
33	12
34	17
35	10
36	23
37	0
38	19
39	14
40	23
41	0
42	29
43	0
44	23
45	20
46	23
47	0
48	31
49	6
50	29
51	18
52	27
53	0
54	35
55	14
56	31
57	20
58	29
59	0
60	43
61	0
62	31
63	26
64	31
65	16
66	45
67	0
68	35
69	24
70	45
71	0
72	47
73	0
74	37
75	34
76	39
77	16
78	53

n	a(n)
1	0
2	0
3	0
4	1
5	0
6	3
7	0
8	3
9	2
10	5
11	0
12	7
13	0
14	7
15	6
16	7
17	0
18	11
19	0
20	11
21	8
22	11
23	0
24	15
25	4
26	13
27	8
28	15
29	0
30	21
31	0
32	15
33	12
34	17
35	10
36	23
37	0
38	19
39	14
40	23
41	0
42	29
43	0
44	23
45	20
46	23
47	0
48	31
49	6
50	29
51	18
52	27
53	0
54	35
55	14
56	31
57	20
58	29
59	0
60	43
61	0
62	31
63	26
64	31
65	16
66	45
67	0
68	35
69	24
70	45
71	0
72	47
73	0
74	37
75	34
76	39
77	16
78	53