A337321 - cp's OEIS frontend

A337321 a(n) is the least number of steps required to reach 1 starting from n under substring substitutions of the form k <-> prime(k) (where prime(k) denotes the k-th prime number).

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

[0, 1, 2, 10, 3, 7, 9, 10, 8, 10, 4, 5, 6, 8, 7, 9, 8, 9, 9, 9, 5, 6, 7, 8, 8, 10, 7, 10, 9, 10, 5, 6, 7, 7, 8, 9, 6, 9, 10, 8, 7, 8, 7, 9, 8, 9, 8, 9, 8, 10, 6, 7, 8, 8, 9, 10, 7, 10, 9, 11, 8, 9, 9, 9, 10, 8, 8, 10, 9, 9, 8, 7, 6, 10, 7, 10, 9, 10, 7, 9, 9, 9]

cp's OEIS Frontend

A337321 a(n) is the least number of steps required to reach 1 starting from n under substring substitutions of the form k <-> prime(k) (where prime(k) denotes the k-th prime number).

Table of values

List of values

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

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

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