A353643 - cp's OEIS frontend

A353643 The greatest common divisor of phi(n) and phi(sigma(n)).

n	a(n)
1	1
2	1
3	2
4	2
5	2
6	2
7	2
8	4
9	6
10	2
11	2
12	4
13	6
14	2
15	8
16	2
17	2
18	6
19	2
20	4
21	4
22	2
23	2
24	8
25	10
26	12
27	2
28	12
29	4
30	8
31	2
32	4
33	4
34	2
35	8
36	12
37	18
38	2
39	24
40	8
41	4
42	4
43	2
44	4
45	24
46	2
47	2
48	4
49	6
50	20
51	8
52	6
53	2
54	2
55	8
56	8
57	4
58	4
59	2
60	16
61	30
62	2
63	12
64	2
65	24
66	4
67	2
68	4
69	4
70	24
71	2
72	24
73	36
74	36
75	20
76	12
77	4
78	24
79	2
80	4
81	2
82	4
83	2
84	24
85	4
86	2
87	8
88	8
89	8
90	24
91	24
92	4
93	4
94	2
95	8
96	8
97	6
98	6

[1, 1, 2, 2, 2, 2, 2, 4, 6, 2, 2, 4, 6, 2, 8, 2, 2, 6, 2, 4, 4, 2, 2, 8, 10, 12, 2, 12, 4, 8, 2, 4, 4, 2, 8, 12, 18, 2, 24, 8, 4, 4, 2, 4, 24, 2, 2, 4, 6, 20, 8, 6, 2, 2, 8, 8, 4, 4, 2, 16, 30, 2, 12, 2, 24, 4, 2, 4, 4, 24, 2, 24, 36, 36, 20, 12, 4, 24, 2, 4, 2, 4, 2, 24, 4, 2, 8, 8, 8, 24, 24, 4, 4, 2, 8, 8, 6, 6]

cp's OEIS Frontend

A353643 The greatest common divisor of phi(n) and phi(sigma(n)).

Table of values

List of values

n	a(n)
1	1
2	1
3	2
4	2
5	2
6	2
7	2
8	4
9	6
10	2
11	2
12	4
13	6
14	2
15	8
16	2
17	2
18	6
19	2
20	4
21	4
22	2
23	2
24	8
25	10
26	12
27	2
28	12
29	4
30	8
31	2
32	4
33	4
34	2
35	8
36	12
37	18
38	2
39	24
40	8
41	4
42	4
43	2
44	4
45	24
46	2
47	2
48	4
49	6
50	20
51	8
52	6
53	2
54	2
55	8
56	8
57	4
58	4
59	2
60	16
61	30
62	2
63	12
64	2
65	24
66	4
67	2
68	4
69	4
70	24
71	2
72	24
73	36
74	36
75	20
76	12
77	4
78	24
79	2
80	4
81	2
82	4
83	2
84	24
85	4
86	2
87	8
88	8
89	8
90	24
91	24
92	4
93	4
94	2
95	8
96	8
97	6
98	6

n	a(n)
1	1
2	1
3	2
4	2
5	2
6	2
7	2
8	4
9	6
10	2
11	2
12	4
13	6
14	2
15	8
16	2
17	2
18	6
19	2
20	4
21	4
22	2
23	2
24	8
25	10
26	12
27	2
28	12
29	4
30	8
31	2
32	4
33	4
34	2
35	8
36	12
37	18
38	2
39	24
40	8
41	4
42	4
43	2
44	4
45	24
46	2
47	2
48	4
49	6
50	20
51	8
52	6
53	2
54	2
55	8
56	8
57	4
58	4
59	2
60	16
61	30
62	2
63	12
64	2
65	24
66	4
67	2
68	4
69	4
70	24
71	2
72	24
73	36
74	36
75	20
76	12
77	4
78	24
79	2
80	4
81	2
82	4
83	2
84	24
85	4
86	2
87	8
88	8
89	8
90	24
91	24
92	4
93	4
94	2
95	8
96	8
97	6
98	6

n	a(n)
1	1
2	1
3	2
4	2
5	2
6	2
7	2
8	4
9	6
10	2
11	2
12	4
13	6
14	2
15	8
16	2
17	2
18	6
19	2
20	4
21	4
22	2
23	2
24	8
25	10
26	12
27	2
28	12
29	4
30	8
31	2
32	4
33	4
34	2
35	8
36	12
37	18
38	2
39	24
40	8
41	4
42	4
43	2
44	4
45	24
46	2
47	2
48	4
49	6
50	20
51	8
52	6
53	2
54	2
55	8
56	8
57	4
58	4
59	2
60	16
61	30
62	2
63	12
64	2
65	24
66	4
67	2
68	4
69	4
70	24
71	2
72	24
73	36
74	36
75	20
76	12
77	4
78	24
79	2
80	4
81	2
82	4
83	2
84	24
85	4
86	2
87	8
88	8
89	8
90	24
91	24
92	4
93	4
94	2
95	8
96	8
97	6
98	6