A252375 - cp's OEIS frontend

A252375 a(n) = smallest r such that r^k <= spf(n) and gpf(n) < r^(k+1), for some k >= 0, where spf and gpf (smallest and greatest prime factor of n) are given by A020639(n) and A006530(n).

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

[2, 2, 2, 2, 2, 2, 2, 2, 2, 6, 2, 2, 2, 8, 3, 2, 2, 2, 2, 6, 3, 12, 2, 2, 2, 14, 2, 8, 2, 6, 2, 2, 12, 18, 2, 2, 2, 20, 14, 6, 2, 8, 2, 12, 3, 24, 2, 2, 2, 6, 18, 14, 2, 2, 4, 8, 20, 30, 2, 6, 2, 32, 3, 2, 4, 12, 2, 18, 24, 8, 2, 2, 2, 38, 3, 20, 4, 14, 2, 6, 2, 42, 2, 8, 5, 44, 30, 12, 2, 6, 4, 24, 32]

cp's OEIS Frontend

A252375 a(n) = smallest r such that r^k <= spf(n) and gpf(n) < r^(k+1), for some k >= 0, where spf and gpf (smallest and greatest prime factor of n) are given by A020639(n) and A006530(n).

Table of values

List of values

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

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

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