A342257 - cp's OEIS frontend

A342257 Period of the sequence {gcd(n, Phi_n(a)): a in Z}, where Phi_n is the n-th cyclotomic polynomial.

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

[1, 2, 3, 2, 5, 3, 7, 2, 3, 5, 11, 1, 13, 7, 1, 2, 17, 3, 19, 5, 7, 11, 23, 1, 5, 13, 3, 1, 29, 1, 31, 2, 1, 17, 1, 1, 37, 19, 13, 1, 41, 7, 43, 1, 1, 23, 47, 1, 7, 5, 1, 13, 53, 3, 11, 1, 19, 29, 59, 1, 61, 31, 1, 2, 1, 1, 67, 17, 1, 1, 71, 1, 73, 37, 1]

cp's OEIS Frontend

A342257 Period of the sequence {gcd(n, Phi_n(a)): a in Z}, where Phi_n is the n-th cyclotomic polynomial.

Table of values

List of values

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

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

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