A133779 - cp's OEIS frontend

A133779 Irregular array: n-th row lists the "isolated divisors" of n. A positive divisor k of n is isolated if neither k-1 nor k+1 divides n.

n	a(n)
1	1
2	0
3	1
4	3
5	4
6	1
7	5
8	6
9	1
10	7
11	4
12	8
13	1
14	3
15	9
16	5
17	10
18	1
19	11
20	6
21	12
22	1
23	13
24	7
25	14
26	1
27	3
28	5
29	15
30	4
31	8
32	16
33	1
34	17
35	6
36	9
37	18
38	1
39	19
40	10
41	20
42	1
43	3
44	7
45	21
46	11
47	22
48	1
49	23
50	6
51	8
52	12
53	24
54	1
55	5
56	25
57	13
58	26
59	1
60	3
61	9
62	27
63	4
64	7
65	14
66	28
67	1
68	29
69	10
70	15
71	30
72	1
73	31
74	4
75	8
76	16
77	32
78	1
79	3
80	11
81	33
82	17
83	34
84	1
85	5
86	7
87	35
88	6

[1, 0, 1, 3, 4, 1, 5, 6, 1, 7, 4, 8, 1, 3, 9, 5, 10, 1, 11, 6, 12, 1, 13, 7, 14, 1, 3, 5, 15, 4, 8, 16, 1, 17, 6, 9, 18, 1, 19, 10, 20, 1, 3, 7, 21, 11, 22, 1, 23, 6, 8, 12, 24, 1, 5, 25, 13, 26, 1, 3, 9, 27, 4, 7, 14, 28, 1, 29, 10, 15, 30, 1, 31, 4, 8, 16, 32, 1, 3, 11, 33, 17, 34, 1, 5, 7, 35, 6]

cp's OEIS Frontend

A133779 Irregular array: n-th row lists the "isolated divisors" of n. A positive divisor k of n is isolated if neither k-1 nor k+1 divides n.

Table of values

List of values

n	a(n)
1	1
2	0
3	1
4	3
5	4
6	1
7	5
8	6
9	1
10	7
11	4
12	8
13	1
14	3
15	9
16	5
17	10
18	1
19	11
20	6
21	12
22	1
23	13
24	7
25	14
26	1
27	3
28	5
29	15
30	4
31	8
32	16
33	1
34	17
35	6
36	9
37	18
38	1
39	19
40	10
41	20
42	1
43	3
44	7
45	21
46	11
47	22
48	1
49	23
50	6
51	8
52	12
53	24
54	1
55	5
56	25
57	13
58	26
59	1
60	3
61	9
62	27
63	4
64	7
65	14
66	28
67	1
68	29
69	10
70	15
71	30
72	1
73	31
74	4
75	8
76	16
77	32
78	1
79	3
80	11
81	33
82	17
83	34
84	1
85	5
86	7
87	35
88	6

n	a(n)
1	1
2	0
3	1
4	3
5	4
6	1
7	5
8	6
9	1
10	7
11	4
12	8
13	1
14	3
15	9
16	5
17	10
18	1
19	11
20	6
21	12
22	1
23	13
24	7
25	14
26	1
27	3
28	5
29	15
30	4
31	8
32	16
33	1
34	17
35	6
36	9
37	18
38	1
39	19
40	10
41	20
42	1
43	3
44	7
45	21
46	11
47	22
48	1
49	23
50	6
51	8
52	12
53	24
54	1
55	5
56	25
57	13
58	26
59	1
60	3
61	9
62	27
63	4
64	7
65	14
66	28
67	1
68	29
69	10
70	15
71	30
72	1
73	31
74	4
75	8
76	16
77	32
78	1
79	3
80	11
81	33
82	17
83	34
84	1
85	5
86	7
87	35
88	6

n	a(n)
1	1
2	0
3	1
4	3
5	4
6	1
7	5
8	6
9	1
10	7
11	4
12	8
13	1
14	3
15	9
16	5
17	10
18	1
19	11
20	6
21	12
22	1
23	13
24	7
25	14
26	1
27	3
28	5
29	15
30	4
31	8
32	16
33	1
34	17
35	6
36	9
37	18
38	1
39	19
40	10
41	20
42	1
43	3
44	7
45	21
46	11
47	22
48	1
49	23
50	6
51	8
52	12
53	24
54	1
55	5
56	25
57	13
58	26
59	1
60	3
61	9
62	27
63	4
64	7
65	14
66	28
67	1
68	29
69	10
70	15
71	30
72	1
73	31
74	4
75	8
76	16
77	32
78	1
79	3
80	11
81	33
82	17
83	34
84	1
85	5
86	7
87	35
88	6