A133829 - cp's OEIS frontend

A133829 a(n) = the largest "non-isolated divisor" of 2n. A positive divisor k of n is non-isolated if k-1 or k+1 also divides n.

n	a(n)
1	2
2	2
3	3
4	2
5	2
6	4
7	2
8	2
9	3
10	5
11	2
12	4
13	2
14	2
15	6
16	2
17	2
18	4
19	2
20	5
21	7
22	2
23	2
24	4
25	2
26	2
27	3
28	8
29	2
30	6
31	2
32	2
33	3
34	2
35	2
36	9
37	2
38	2
39	3
40	5
41	2
42	7
43	2
44	2
45	10
46	2
47	2
48	4
49	2
50	5
51	3
52	2
53	2
54	4
55	11
56	8
57	3
58	2
59	2
60	6
61	2
62	2
63	7
64	2
65	2
66	12
67	2
68	2
69	3
70	5
71	2
72	9
73	2
74	2
75	6
76	2
77	2
78	13
79	2
80	5
81	3
82	2
83	2
84	8
85	2
86	2
87	3
88	2
89	2
90	10
91	14
92	2
93	3
94	2
95	2
96	4
97	2
98	2
99	3

[2, 2, 3, 2, 2, 4, 2, 2, 3, 5, 2, 4, 2, 2, 6, 2, 2, 4, 2, 5, 7, 2, 2, 4, 2, 2, 3, 8, 2, 6, 2, 2, 3, 2, 2, 9, 2, 2, 3, 5, 2, 7, 2, 2, 10, 2, 2, 4, 2, 5, 3, 2, 2, 4, 11, 8, 3, 2, 2, 6, 2, 2, 7, 2, 2, 12, 2, 2, 3, 5, 2, 9, 2, 2, 6, 2, 2, 13, 2, 5, 3, 2, 2, 8, 2, 2, 3, 2, 2, 10, 14, 2, 3, 2, 2, 4, 2, 2, 3]

cp's OEIS Frontend

A133829 a(n) = the largest "non-isolated divisor" of 2n. A positive divisor k of n is non-isolated if k-1 or k+1 also divides n.

Table of values

List of values

n	a(n)
1	2
2	2
3	3
4	2
5	2
6	4
7	2
8	2
9	3
10	5
11	2
12	4
13	2
14	2
15	6
16	2
17	2
18	4
19	2
20	5
21	7
22	2
23	2
24	4
25	2
26	2
27	3
28	8
29	2
30	6
31	2
32	2
33	3
34	2
35	2
36	9
37	2
38	2
39	3
40	5
41	2
42	7
43	2
44	2
45	10
46	2
47	2
48	4
49	2
50	5
51	3
52	2
53	2
54	4
55	11
56	8
57	3
58	2
59	2
60	6
61	2
62	2
63	7
64	2
65	2
66	12
67	2
68	2
69	3
70	5
71	2
72	9
73	2
74	2
75	6
76	2
77	2
78	13
79	2
80	5
81	3
82	2
83	2
84	8
85	2
86	2
87	3
88	2
89	2
90	10
91	14
92	2
93	3
94	2
95	2
96	4
97	2
98	2
99	3

n	a(n)
1	2
2	2
3	3
4	2
5	2
6	4
7	2
8	2
9	3
10	5
11	2
12	4
13	2
14	2
15	6
16	2
17	2
18	4
19	2
20	5
21	7
22	2
23	2
24	4
25	2
26	2
27	3
28	8
29	2
30	6
31	2
32	2
33	3
34	2
35	2
36	9
37	2
38	2
39	3
40	5
41	2
42	7
43	2
44	2
45	10
46	2
47	2
48	4
49	2
50	5
51	3
52	2
53	2
54	4
55	11
56	8
57	3
58	2
59	2
60	6
61	2
62	2
63	7
64	2
65	2
66	12
67	2
68	2
69	3
70	5
71	2
72	9
73	2
74	2
75	6
76	2
77	2
78	13
79	2
80	5
81	3
82	2
83	2
84	8
85	2
86	2
87	3
88	2
89	2
90	10
91	14
92	2
93	3
94	2
95	2
96	4
97	2
98	2
99	3

n	a(n)
1	2
2	2
3	3
4	2
5	2
6	4
7	2
8	2
9	3
10	5
11	2
12	4
13	2
14	2
15	6
16	2
17	2
18	4
19	2
20	5
21	7
22	2
23	2
24	4
25	2
26	2
27	3
28	8
29	2
30	6
31	2
32	2
33	3
34	2
35	2
36	9
37	2
38	2
39	3
40	5
41	2
42	7
43	2
44	2
45	10
46	2
47	2
48	4
49	2
50	5
51	3
52	2
53	2
54	4
55	11
56	8
57	3
58	2
59	2
60	6
61	2
62	2
63	7
64	2
65	2
66	12
67	2
68	2
69	3
70	5
71	2
72	9
73	2
74	2
75	6
76	2
77	2
78	13
79	2
80	5
81	3
82	2
83	2
84	8
85	2
86	2
87	3
88	2
89	2
90	10
91	14
92	2
93	3
94	2
95	2
96	4
97	2
98	2
99	3