A117365 - cp's OEIS frontend

A117365 a(n) = largest prime less than the smallest prime dividing n (or 1 if there is no such prime).

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

[1, 1, 2, 1, 3, 1, 5, 1, 2, 1, 7, 1, 11, 1, 2, 1, 13, 1, 17, 1, 2, 1, 19, 1, 3, 1, 2, 1, 23, 1, 29, 1, 2, 1, 3, 1, 31, 1, 2, 1, 37, 1, 41, 1, 2, 1, 43, 1, 5, 1, 2, 1, 47, 1, 3, 1, 2, 1, 53, 1, 59, 1, 2, 1, 3, 1, 61, 1, 2, 1, 67, 1, 71, 1, 2, 1, 5, 1, 73, 1, 2, 1, 79, 1, 3, 1, 2, 1, 83, 1, 5, 1, 2, 1, 3, 1]

cp's OEIS Frontend

A117365 a(n) = largest prime less than the smallest prime dividing n (or 1 if there is no such prime).

Table of values

List of values

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

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

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