A175264 - cp's OEIS frontend

A175264 a(n) = the middle prime among the distinct primes dividing {the n-th positive integer divisible by exactly an odd number of distinct primes}.

n	a(n)
1	2
2	3
3	2
4	5
5	7
6	2
7	3
8	11
9	13
10	2
11	17
12	19
13	23
14	5
15	3
16	29
17	3
18	31
19	2
20	37
21	41
22	3
23	43
24	47
25	7
26	53
27	59
28	3
29	61
30	2
31	3
32	67
33	5
34	71
35	73
36	3
37	79
38	3
39	83
40	3
41	89
42	3
43	97
44	101
45	3
46	103
47	5
48	107
49	109
50	5
51	113
52	3
53	3
54	11
55	5
56	3
57	127
58	2
59	5
60	131
61	3
62	137
63	3
64	139
65	5
66	149
67	3
68	151
69	7
70	3
71	157
72	163
73	5
74	167
75	3
76	13
77	5
78	173
79	3

[2, 3, 2, 5, 7, 2, 3, 11, 13, 2, 17, 19, 23, 5, 3, 29, 3, 31, 2, 37, 41, 3, 43, 47, 7, 53, 59, 3, 61, 2, 3, 67, 5, 71, 73, 3, 79, 3, 83, 3, 89, 3, 97, 101, 3, 103, 5, 107, 109, 5, 113, 3, 3, 11, 5, 3, 127, 2, 5, 131, 3, 137, 3, 139, 5, 149, 3, 151, 7, 3, 157, 163, 5, 167, 3, 13, 5, 173, 3]

cp's OEIS Frontend

A175264 a(n) = the middle prime among the distinct primes dividing {the n-th positive integer divisible by exactly an odd number of distinct primes}.

Table of values

List of values

n	a(n)
1	2
2	3
3	2
4	5
5	7
6	2
7	3
8	11
9	13
10	2
11	17
12	19
13	23
14	5
15	3
16	29
17	3
18	31
19	2
20	37
21	41
22	3
23	43
24	47
25	7
26	53
27	59
28	3
29	61
30	2
31	3
32	67
33	5
34	71
35	73
36	3
37	79
38	3
39	83
40	3
41	89
42	3
43	97
44	101
45	3
46	103
47	5
48	107
49	109
50	5
51	113
52	3
53	3
54	11
55	5
56	3
57	127
58	2
59	5
60	131
61	3
62	137
63	3
64	139
65	5
66	149
67	3
68	151
69	7
70	3
71	157
72	163
73	5
74	167
75	3
76	13
77	5
78	173
79	3

n	a(n)
1	2
2	3
3	2
4	5
5	7
6	2
7	3
8	11
9	13
10	2
11	17
12	19
13	23
14	5
15	3
16	29
17	3
18	31
19	2
20	37
21	41
22	3
23	43
24	47
25	7
26	53
27	59
28	3
29	61
30	2
31	3
32	67
33	5
34	71
35	73
36	3
37	79
38	3
39	83
40	3
41	89
42	3
43	97
44	101
45	3
46	103
47	5
48	107
49	109
50	5
51	113
52	3
53	3
54	11
55	5
56	3
57	127
58	2
59	5
60	131
61	3
62	137
63	3
64	139
65	5
66	149
67	3
68	151
69	7
70	3
71	157
72	163
73	5
74	167
75	3
76	13
77	5
78	173
79	3

n	a(n)
1	2
2	3
3	2
4	5
5	7
6	2
7	3
8	11
9	13
10	2
11	17
12	19
13	23
14	5
15	3
16	29
17	3
18	31
19	2
20	37
21	41
22	3
23	43
24	47
25	7
26	53
27	59
28	3
29	61
30	2
31	3
32	67
33	5
34	71
35	73
36	3
37	79
38	3
39	83
40	3
41	89
42	3
43	97
44	101
45	3
46	103
47	5
48	107
49	109
50	5
51	113
52	3
53	3
54	11
55	5
56	3
57	127
58	2
59	5
60	131
61	3
62	137
63	3
64	139
65	5
66	149
67	3
68	151
69	7
70	3
71	157
72	163
73	5
74	167
75	3
76	13
77	5
78	173
79	3