A217581 - cp's OEIS frontend

A217581 Largest prime divisor of n <= sqrt(n), 1 if n is prime or 1.

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

[1, 1, 1, 2, 1, 2, 1, 2, 3, 2, 1, 3, 1, 2, 3, 2, 1, 3, 1, 2, 3, 2, 1, 3, 5, 2, 3, 2, 1, 5, 1, 2, 3, 2, 5, 3, 1, 2, 3, 5, 1, 3, 1, 2, 5, 2, 1, 3, 7, 5, 3, 2, 1, 3, 5, 7, 3, 2, 1, 5, 1, 2, 7, 2, 5, 3, 1, 2, 3, 7, 1, 3, 1, 2, 5, 2, 7, 3, 1, 5, 3, 2, 1, 7, 5, 2, 3]

cp's OEIS Frontend

A217581 Largest prime divisor of n <= sqrt(n), 1 if n is prime or 1.

Table of values

List of values

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

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

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