A036845 - cp's OEIS frontend

A036845 a(n) = min_{k} {T(n,k)} where T(n,k) is the "phi/sigma tug-of-war sequence with seed n" defined by T(n,1) = phi(n), T(n,2) = sigma(phi(n)), T(n,3) = phi(sigma(phi(n))), ..., T(n,k) = phi(T(n,k-1)) if k is odd and = sigma(T(n,k-1)) if k is even.

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

[1, 1, 2, 2, 4, 2, 4, 4, 4, 4, 4, 4, 12, 4, 8, 8, 16, 4, 16, 8, 12, 4, 12, 8, 12, 12, 16, 12, 16, 8, 16, 16, 12, 16, 16, 12, 36, 16, 16, 16, 16, 12, 32, 12, 16, 12, 16, 16, 32, 12, 32, 16, 32, 16, 16, 16, 36, 16, 16, 16, 48, 16, 36, 32, 48, 12, 48, 32, 16, 16, 48, 16, 72, 36, 16]

cp's OEIS Frontend

A036845 a(n) = min_{k} {T(n,k)} where T(n,k) is the "phi/sigma tug-of-war sequence with seed n" defined by T(n,1) = phi(n), T(n,2) = sigma(phi(n)), T(n,3) = phi(sigma(phi(n))), ..., T(n,k) = phi(T(n,k-1)) if k is odd and = sigma(T(n,k-1)) if k is even.

Table of values

List of values

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

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

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