A360257 - cp's OEIS frontend

A360257 a(1) = 1; for n > 1, a(n) is the number of preceding terms having the same sum of divisors as a(n-1).

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

[1, 1, 2, 1, 3, 1, 4, 1, 5, 1, 6, 1, 7, 1, 8, 1, 9, 1, 10, 1, 11, 2, 2, 3, 2, 4, 2, 5, 2, 6, 3, 3, 4, 3, 5, 3, 6, 4, 4, 5, 4, 6, 5, 5, 6, 6, 7, 2, 7, 3, 7, 4, 7, 5, 7, 6, 8, 2, 8, 3, 8, 4, 8, 5, 8, 6, 9, 2, 9, 3, 9, 4, 9, 5, 9, 6, 10, 2, 10, 3, 10, 4, 10, 5, 10, 6, 11, 12, 1, 12, 2, 11, 13, 1]

cp's OEIS Frontend

A360257 a(1) = 1; for n > 1, a(n) is the number of preceding terms having the same sum of divisors as a(n-1).

Table of values

List of values

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

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

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