A074970 - cp's OEIS frontend

A074970 Number of steps to reach the first integer starting with sigma(n)/n and iterating the map x -> x*ceiling(x), or -1 if no integer is ever reached.

n	a(n)
1	0
2	1
3	2
4	2
5	18
6	0
7	3
8	2
9	3
10	3
11	26
12	1
13	9
14	3
15	7
16	3
17	6
18	3
19	56
20	10
21	9
22	15
23	42
24	2
25	10
26	3
27	3
28	0
29	38
30	17
31	79
32	3
33	27
34	16
35	8
36	8
37	200
38	76
39	4
40	3
41	36
42	2
43	4
44	15
45	4
46	51
47	11
48	2
49	4
50	6
51	22
52	42
53	43
54	5
55	25
56	2
57	4
58	103
59	37
60	17
61	18
62	20
63	8
64	3
65	22
66	25
67	225
68	59
69	6
70	13
71	20
72	4
73	182
74	13
75	8

[0, 1, 2, 2, 18, 0, 3, 2, 3, 3, 26, 1, 9, 3, 7, 3, 6, 3, 56, 10, 9, 15, 42, 2, 10, 3, 3, 0, 38, 17, 79, 3, 27, 16, 8, 8, 200, 76, 4, 3, 36, 2, 4, 15, 4, 51, 11, 2, 4, 6, 22, 42, 43, 5, 25, 2, 4, 103, 37, 17, 18, 20, 8, 3, 22, 25, 225, 59, 6, 13, 20, 4, 182, 13, 8]

cp's OEIS Frontend

A074970 Number of steps to reach the first integer starting with sigma(n)/n and iterating the map x -> x*ceiling(x), or -1 if no integer is ever reached.

Table of values

List of values

n	a(n)
1	0
2	1
3	2
4	2
5	18
6	0
7	3
8	2
9	3
10	3
11	26
12	1
13	9
14	3
15	7
16	3
17	6
18	3
19	56
20	10
21	9
22	15
23	42
24	2
25	10
26	3
27	3
28	0
29	38
30	17
31	79
32	3
33	27
34	16
35	8
36	8
37	200
38	76
39	4
40	3
41	36
42	2
43	4
44	15
45	4
46	51
47	11
48	2
49	4
50	6
51	22
52	42
53	43
54	5
55	25
56	2
57	4
58	103
59	37
60	17
61	18
62	20
63	8
64	3
65	22
66	25
67	225
68	59
69	6
70	13
71	20
72	4
73	182
74	13
75	8

n	a(n)
1	0
2	1
3	2
4	2
5	18
6	0
7	3
8	2
9	3
10	3
11	26
12	1
13	9
14	3
15	7
16	3
17	6
18	3
19	56
20	10
21	9
22	15
23	42
24	2
25	10
26	3
27	3
28	0
29	38
30	17
31	79
32	3
33	27
34	16
35	8
36	8
37	200
38	76
39	4
40	3
41	36
42	2
43	4
44	15
45	4
46	51
47	11
48	2
49	4
50	6
51	22
52	42
53	43
54	5
55	25
56	2
57	4
58	103
59	37
60	17
61	18
62	20
63	8
64	3
65	22
66	25
67	225
68	59
69	6
70	13
71	20
72	4
73	182
74	13
75	8

n	a(n)
1	0
2	1
3	2
4	2
5	18
6	0
7	3
8	2
9	3
10	3
11	26
12	1
13	9
14	3
15	7
16	3
17	6
18	3
19	56
20	10
21	9
22	15
23	42
24	2
25	10
26	3
27	3
28	0
29	38
30	17
31	79
32	3
33	27
34	16
35	8
36	8
37	200
38	76
39	4
40	3
41	36
42	2
43	4
44	15
45	4
46	51
47	11
48	2
49	4
50	6
51	22
52	42
53	43
54	5
55	25
56	2
57	4
58	103
59	37
60	17
61	18
62	20
63	8
64	3
65	22
66	25
67	225
68	59
69	6
70	13
71	20
72	4
73	182
74	13
75	8