A085021 - cp's OEIS frontend

A085021 Number of prime factors of cyclotomic(n,2), which is A019320(n), the value of the n-th cyclotomic polynomial evaluated at x=2.

n	a(n)
1	0
2	1
3	1
4	1
5	1
6	1
7	1
8	1
9	1
10	1
11	2
12	1
13	1
14	1
15	1
16	1
17	1
18	2
19	1
20	2
21	2
22	1
23	2
24	1
25	2
26	1
27	1
28	2
29	3
30	1
31	1
32	1
33	1
34	1
35	2
36	2
37	2
38	1
39	2
40	1
41	2
42	1
43	3
44	2
45	2
46	1
47	3
48	2
49	1
50	2
51	3
52	3
53	3
54	2
55	3
56	1
57	2
58	2
59	2
60	2
61	1
62	1
63	2
64	2
65	1
66	2
67	2
68	3
69	1
70	2
71	3
72	2
73	3
74	2
75	2
76	3
77	1
78	1
79	3
80	1
81	3
82	2
83	2
84	2
85	1
86	1
87	2
88	2
89	1
90	1
91	3
92	4
93	1
94	2
95	3
96	2
97	2
98	1
99	3
100	4

[0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 2, 1, 2, 2, 1, 2, 1, 2, 1, 1, 2, 3, 1, 1, 1, 1, 1, 2, 2, 2, 1, 2, 1, 2, 1, 3, 2, 2, 1, 3, 2, 1, 2, 3, 3, 3, 2, 3, 1, 2, 2, 2, 2, 1, 1, 2, 2, 1, 2, 2, 3, 1, 2, 3, 2, 3, 2, 2, 3, 1, 1, 3, 1, 3, 2, 2, 2, 1, 1, 2, 2, 1, 1, 3, 4, 1, 2, 3, 2, 2, 1, 3, 4]

cp's OEIS Frontend

A085021 Number of prime factors of cyclotomic(n,2), which is A019320(n), the value of the n-th cyclotomic polynomial evaluated at x=2.

Table of values

List of values

n	a(n)
1	0
2	1
3	1
4	1
5	1
6	1
7	1
8	1
9	1
10	1
11	2
12	1
13	1
14	1
15	1
16	1
17	1
18	2
19	1
20	2
21	2
22	1
23	2
24	1
25	2
26	1
27	1
28	2
29	3
30	1
31	1
32	1
33	1
34	1
35	2
36	2
37	2
38	1
39	2
40	1
41	2
42	1
43	3
44	2
45	2
46	1
47	3
48	2
49	1
50	2
51	3
52	3
53	3
54	2
55	3
56	1
57	2
58	2
59	2
60	2
61	1
62	1
63	2
64	2
65	1
66	2
67	2
68	3
69	1
70	2
71	3
72	2
73	3
74	2
75	2
76	3
77	1
78	1
79	3
80	1
81	3
82	2
83	2
84	2
85	1
86	1
87	2
88	2
89	1
90	1
91	3
92	4
93	1
94	2
95	3
96	2
97	2
98	1
99	3
100	4

n	a(n)
1	0
2	1
3	1
4	1
5	1
6	1
7	1
8	1
9	1
10	1
11	2
12	1
13	1
14	1
15	1
16	1
17	1
18	2
19	1
20	2
21	2
22	1
23	2
24	1
25	2
26	1
27	1
28	2
29	3
30	1
31	1
32	1
33	1
34	1
35	2
36	2
37	2
38	1
39	2
40	1
41	2
42	1
43	3
44	2
45	2
46	1
47	3
48	2
49	1
50	2
51	3
52	3
53	3
54	2
55	3
56	1
57	2
58	2
59	2
60	2
61	1
62	1
63	2
64	2
65	1
66	2
67	2
68	3
69	1
70	2
71	3
72	2
73	3
74	2
75	2
76	3
77	1
78	1
79	3
80	1
81	3
82	2
83	2
84	2
85	1
86	1
87	2
88	2
89	1
90	1
91	3
92	4
93	1
94	2
95	3
96	2
97	2
98	1
99	3
100	4

n	a(n)
1	0
2	1
3	1
4	1
5	1
6	1
7	1
8	1
9	1
10	1
11	2
12	1
13	1
14	1
15	1
16	1
17	1
18	2
19	1
20	2
21	2
22	1
23	2
24	1
25	2
26	1
27	1
28	2
29	3
30	1
31	1
32	1
33	1
34	1
35	2
36	2
37	2
38	1
39	2
40	1
41	2
42	1
43	3
44	2
45	2
46	1
47	3
48	2
49	1
50	2
51	3
52	3
53	3
54	2
55	3
56	1
57	2
58	2
59	2
60	2
61	1
62	1
63	2
64	2
65	1
66	2
67	2
68	3
69	1
70	2
71	3
72	2
73	3
74	2
75	2
76	3
77	1
78	1
79	3
80	1
81	3
82	2
83	2
84	2
85	1
86	1
87	2
88	2
89	1
90	1
91	3
92	4
93	1
94	2
95	3
96	2
97	2
98	1
99	3
100	4