A159908 - cp's OEIS frontend

A159908 Number of pairs (p,q) of primes p <= q <= r=prime(n) such that the cyclotomic polynomial Phi(pqr) has no coefficient > 1 in absolute value.

n	a(n)
1	1
2	3
3	6
4	9
5	13
6	15
7	19
8	23
9	27
10	30
11	34
12	35
13	43
14	40
15	45
16	47
17	54
18	57
19	58
20	64
21	69
22	69
23	71
24	79
25	79
26	84
27	86
28	87
29	97
30	96
31	94
32	107
33	106
34	109
35	120
36	111
37	120
38	123
39	124
40	133
41	135
42	134
43	144
44	143
45	143
46	154
47	154
48	154
49	163
50	161
51	167
52	175
53	174
54	175
55	179
56	183
57	187
58	191
59	193
60	199
61	197
62	202
63	203

[1, 3, 6, 9, 13, 15, 19, 23, 27, 30, 34, 35, 43, 40, 45, 47, 54, 57, 58, 64, 69, 69, 71, 79, 79, 84, 86, 87, 97, 96, 94, 107, 106, 109, 120, 111, 120, 123, 124, 133, 135, 134, 144, 143, 143, 154, 154, 154, 163, 161, 167, 175, 174, 175, 179, 183, 187, 191, 193, 199, 197, 202, 203]

cp's OEIS Frontend

A159908 Number of pairs (p,q) of 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	1
2	3
3	6
4	9
5	13
6	15
7	19
8	23
9	27
10	30
11	34
12	35
13	43
14	40
15	45
16	47
17	54
18	57
19	58
20	64
21	69
22	69
23	71
24	79
25	79
26	84
27	86
28	87
29	97
30	96
31	94
32	107
33	106
34	109
35	120
36	111
37	120
38	123
39	124
40	133
41	135
42	134
43	144
44	143
45	143
46	154
47	154
48	154
49	163
50	161
51	167
52	175
53	174
54	175
55	179
56	183
57	187
58	191
59	193
60	199
61	197
62	202
63	203

n	a(n)
1	1
2	3
3	6
4	9
5	13
6	15
7	19
8	23
9	27
10	30
11	34
12	35
13	43
14	40
15	45
16	47
17	54
18	57
19	58
20	64
21	69
22	69
23	71
24	79
25	79
26	84
27	86
28	87
29	97
30	96
31	94
32	107
33	106
34	109
35	120
36	111
37	120
38	123
39	124
40	133
41	135
42	134
43	144
44	143
45	143
46	154
47	154
48	154
49	163
50	161
51	167
52	175
53	174
54	175
55	179
56	183
57	187
58	191
59	193
60	199
61	197
62	202
63	203

cp's OEIS Frontend

A159908 Number of pairs (p,q) of 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

A159908 Number of pairs (p,q) of primes p <= q <= r=prime(n) such that the cyclotomic polynomial Phi(pqr) has no coefficient > 1 in absolute value.

n	a(n)
1	1
2	3
3	6
4	9
5	13
6	15
7	19
8	23
9	27
10	30
11	34
12	35
13	43
14	40
15	45
16	47
17	54
18	57
19	58
20	64
21	69
22	69
23	71
24	79
25	79
26	84
27	86
28	87
29	97
30	96
31	94
32	107
33	106
34	109
35	120
36	111
37	120
38	123
39	124
40	133
41	135
42	134
43	144
44	143
45	143
46	154
47	154
48	154
49	163
50	161
51	167
52	175
53	174
54	175
55	179
56	183
57	187
58	191
59	193
60	199
61	197
62	202
63	203