A293516 - cp's OEIS frontend

A293516 a(n) = phi(n) - 2*phi(phi(n)), where phi = Euler totient function, A000010.

n	a(n)
1	-1
2	-1
3	0
4	0
5	0
6	0
7	2
8	0
9	2
10	0
11	2
12	0
13	4
14	2
15	0
16	0
17	0
18	2
19	6
20	0
21	4
22	2
23	2
24	0
25	4
26	4
27	6
28	4
29	4
30	0
31	14
32	0
33	4
34	0
35	8
36	4
37	12
38	6
39	8
40	0
41	8
42	4
43	18
44	4
45	8
46	2
47	2
48	0
49	18
50	4
51	0
52	8
53	4
54	6
55	8
56	8
57	12
58	4
59	2
60	0
61	28
62	14
63	12
64	0
65	16
66	4
67	26
68	0
69	4
70	8
71	22
72	8
73	24
74	12
75	8
76	12
77	28
78	8
79	30
80	0
81	18
82	8
83	2
84	8
85	0
86	18
87	8
88	8
89	8
90	8
91	24
92	4
93	28
94	2
95	24
96	0
97	32

[-1, -1, 0, 0, 0, 0, 2, 0, 2, 0, 2, 0, 4, 2, 0, 0, 0, 2, 6, 0, 4, 2, 2, 0, 4, 4, 6, 4, 4, 0, 14, 0, 4, 0, 8, 4, 12, 6, 8, 0, 8, 4, 18, 4, 8, 2, 2, 0, 18, 4, 0, 8, 4, 6, 8, 8, 12, 4, 2, 0, 28, 14, 12, 0, 16, 4, 26, 0, 4, 8, 22, 8, 24, 12, 8, 12, 28, 8, 30, 0, 18, 8, 2, 8, 0, 18, 8, 8, 8, 8, 24, 4, 28, 2, 24, 0, 32]

cp's OEIS Frontend

A293516 a(n) = phi(n) - 2*phi(phi(n)), where phi = Euler totient function, A000010.

Table of values

List of values

n	a(n)
1	-1
2	-1
3	0
4	0
5	0
6	0
7	2
8	0
9	2
10	0
11	2
12	0
13	4
14	2
15	0
16	0
17	0
18	2
19	6
20	0
21	4
22	2
23	2
24	0
25	4
26	4
27	6
28	4
29	4
30	0
31	14
32	0
33	4
34	0
35	8
36	4
37	12
38	6
39	8
40	0
41	8
42	4
43	18
44	4
45	8
46	2
47	2
48	0
49	18
50	4
51	0
52	8
53	4
54	6
55	8
56	8
57	12
58	4
59	2
60	0
61	28
62	14
63	12
64	0
65	16
66	4
67	26
68	0
69	4
70	8
71	22
72	8
73	24
74	12
75	8
76	12
77	28
78	8
79	30
80	0
81	18
82	8
83	2
84	8
85	0
86	18
87	8
88	8
89	8
90	8
91	24
92	4
93	28
94	2
95	24
96	0
97	32

n	a(n)
1	-1
2	-1
3	0
4	0
5	0
6	0
7	2
8	0
9	2
10	0
11	2
12	0
13	4
14	2
15	0
16	0
17	0
18	2
19	6
20	0
21	4
22	2
23	2
24	0
25	4
26	4
27	6
28	4
29	4
30	0
31	14
32	0
33	4
34	0
35	8
36	4
37	12
38	6
39	8
40	0
41	8
42	4
43	18
44	4
45	8
46	2
47	2
48	0
49	18
50	4
51	0
52	8
53	4
54	6
55	8
56	8
57	12
58	4
59	2
60	0
61	28
62	14
63	12
64	0
65	16
66	4
67	26
68	0
69	4
70	8
71	22
72	8
73	24
74	12
75	8
76	12
77	28
78	8
79	30
80	0
81	18
82	8
83	2
84	8
85	0
86	18
87	8
88	8
89	8
90	8
91	24
92	4
93	28
94	2
95	24
96	0
97	32

n	a(n)
1	-1
2	-1
3	0
4	0
5	0
6	0
7	2
8	0
9	2
10	0
11	2
12	0
13	4
14	2
15	0
16	0
17	0
18	2
19	6
20	0
21	4
22	2
23	2
24	0
25	4
26	4
27	6
28	4
29	4
30	0
31	14
32	0
33	4
34	0
35	8
36	4
37	12
38	6
39	8
40	0
41	8
42	4
43	18
44	4
45	8
46	2
47	2
48	0
49	18
50	4
51	0
52	8
53	4
54	6
55	8
56	8
57	12
58	4
59	2
60	0
61	28
62	14
63	12
64	0
65	16
66	4
67	26
68	0
69	4
70	8
71	22
72	8
73	24
74	12
75	8
76	12
77	28
78	8
79	30
80	0
81	18
82	8
83	2
84	8
85	0
86	18
87	8
88	8
89	8
90	8
91	24
92	4
93	28
94	2
95	24
96	0
97	32