A379119 - cp's OEIS frontend

A379119 a(1) = 1; for n > 1, a(n) is the smallest unitary divisor d > 1 of n such that A048720(A065621(sigma(n/d)),sigma(d)) is equal to sigma(n).

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

[1, 2, 3, 4, 5, 2, 7, 8, 9, 2, 11, 4, 13, 2, 5, 16, 17, 18, 19, 4, 3, 2, 23, 8, 25, 13, 27, 4, 29, 2, 31, 32, 11, 34, 5, 36, 37, 38, 13, 8, 41, 2, 43, 4, 45, 2, 47, 16, 49, 25, 17, 4, 53, 54, 5, 8, 19, 29, 59, 4, 61, 2, 9, 64, 13, 2, 67, 68, 23, 2, 71, 8, 73, 74, 25, 4, 11, 13, 79, 16, 81, 82, 83, 4, 85, 2, 29, 8, 89]

cp's OEIS Frontend

A379119 a(1) = 1; for n > 1, a(n) is the smallest unitary divisor d > 1 of n such that A048720(A065621(sigma(n/d)),sigma(d)) is equal to sigma(n).

Table of values

List of values

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

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

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