A159909 - cp's OEIS frontend

A159909 Number of pairs (p,q) of odd primes p < q < r=prime(n) such that the cyclotomic polynomial Phi(pqr) has no coefficient > 1 in absolute value.

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

[0, 0, 0, 0, 1, 0, 1, 2, 3, 3, 4, 2, 7, 1, 3, 2, 6, 6, 4, 7, 9, 6, 5, 10, 7, 9, 8, 6, 13, 9, 4, 14, 10, 10, 18, 6, 12, 12, 10, 16, 15, 11, 18, 14, 11, 19, 16, 13, 19, 14, 17, 22, 18, 16, 17, 18, 19, 20, 19, 22, 17, 19, 17, 19, 19, 19, 31, 25, 13, 38, 20, 23, 25, 23, 31, 30, 31, 19]

cp's OEIS Frontend

A159909 Number of pairs (p,q) of odd primes p < q < r=prime(n) such that the cyclotomic polynomial Phi(pqr) has no coefficient > 1 in absolute value.

Table of values

List of values

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

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

cp's OEIS Frontend

A159909 Number of pairs (p,q) of odd primes p < q < r=prime(n) such that the cyclotomic polynomial Phi(p*q*r) has no coefficient > 1 in absolute value.

Table of values

List of values

A159909 Number of pairs (p,q) of odd primes p < q < r=prime(n) such that the cyclotomic polynomial Phi(pqr) has no coefficient > 1 in absolute value.

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