A175402 - cp's OEIS frontend

A175402 a(n) is the number of iterations of {r -> (((D_1^D_2)^D_3)^...)^D_k, where D_k is the k-th decimal digit of r} needed to reach a one-digit number, starting at r = n.

n	a(n)
0	0
1	0
2	0
3	0
4	0
5	0
6	0
7	0
8	0
9	0
10	1
11	1
12	1
13	1
14	1
15	1
16	1
17	1
18	1
19	1
20	1
21	1
22	1
23	1
24	2
25	2
26	3
27	2
28	3
29	4
30	1
31	1
32	1
33	3
34	2
35	3
36	3
37	3
38	3
39	2
40	1
41	1
42	2
43	3
44	3
45	2
46	2
47	2
48	3
49	3
50	1
51	1
52	3
53	2
54	3
55	3
56	2
57	3
58	2
59	2
60	1
61	1
62	4
63	4
64	2
65	3
66	3
67	3
68	2
69	2
70	1
71	1
72	4
73	4
74	2
75	2
76	2
77	3
78	2
79	2
80	1
81	1
82	3
83	4
84	2
85	3
86	3
87	2
88	2
89	2
90	1
91	1
92	2
93	3
94	3
95	2
96	3
97	3
98	2
99	2
100	1
101	1
102	1
103	1
104	1
105	1
106	1
107	1

[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 3, 2, 3, 4, 1, 1, 1, 3, 2, 3, 3, 3, 3, 2, 1, 1, 2, 3, 3, 2, 2, 2, 3, 3, 1, 1, 3, 2, 3, 3, 2, 3, 2, 2, 1, 1, 4, 4, 2, 3, 3, 3, 2, 2, 1, 1, 4, 4, 2, 2, 2, 3, 2, 2, 1, 1, 3, 4, 2, 3, 3, 2, 2, 2, 1, 1, 2, 3, 3, 2, 3, 3, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1]

cp's OEIS Frontend

A175402 a(n) is the number of iterations of {r -> (((D_1^D_2)^D_3)^...)^D_k, where D_k is the k-th decimal digit of r} needed to reach a one-digit number, starting at r = n.

Table of values

List of values

n	a(n)
0	0
1	0
2	0
3	0
4	0
5	0
6	0
7	0
8	0
9	0
10	1
11	1
12	1
13	1
14	1
15	1
16	1
17	1
18	1
19	1
20	1
21	1
22	1
23	1
24	2
25	2
26	3
27	2
28	3
29	4
30	1
31	1
32	1
33	3
34	2
35	3
36	3
37	3
38	3
39	2
40	1
41	1
42	2
43	3
44	3
45	2
46	2
47	2
48	3
49	3
50	1
51	1
52	3
53	2
54	3
55	3
56	2
57	3
58	2
59	2
60	1
61	1
62	4
63	4
64	2
65	3
66	3
67	3
68	2
69	2
70	1
71	1
72	4
73	4
74	2
75	2
76	2
77	3
78	2
79	2
80	1
81	1
82	3
83	4
84	2
85	3
86	3
87	2
88	2
89	2
90	1
91	1
92	2
93	3
94	3
95	2
96	3
97	3
98	2
99	2
100	1
101	1
102	1
103	1
104	1
105	1
106	1
107	1

n	a(n)
0	0
1	0
2	0
3	0
4	0
5	0
6	0
7	0
8	0
9	0
10	1
11	1
12	1
13	1
14	1
15	1
16	1
17	1
18	1
19	1
20	1
21	1
22	1
23	1
24	2
25	2
26	3
27	2
28	3
29	4
30	1
31	1
32	1
33	3
34	2
35	3
36	3
37	3
38	3
39	2
40	1
41	1
42	2
43	3
44	3
45	2
46	2
47	2
48	3
49	3
50	1
51	1
52	3
53	2
54	3
55	3
56	2
57	3
58	2
59	2
60	1
61	1
62	4
63	4
64	2
65	3
66	3
67	3
68	2
69	2
70	1
71	1
72	4
73	4
74	2
75	2
76	2
77	3
78	2
79	2
80	1
81	1
82	3
83	4
84	2
85	3
86	3
87	2
88	2
89	2
90	1
91	1
92	2
93	3
94	3
95	2
96	3
97	3
98	2
99	2
100	1
101	1
102	1
103	1
104	1
105	1
106	1
107	1

n	a(n)
0	0
1	0
2	0
3	0
4	0
5	0
6	0
7	0
8	0
9	0
10	1
11	1
12	1
13	1
14	1
15	1
16	1
17	1
18	1
19	1
20	1
21	1
22	1
23	1
24	2
25	2
26	3
27	2
28	3
29	4
30	1
31	1
32	1
33	3
34	2
35	3
36	3
37	3
38	3
39	2
40	1
41	1
42	2
43	3
44	3
45	2
46	2
47	2
48	3
49	3
50	1
51	1
52	3
53	2
54	3
55	3
56	2
57	3
58	2
59	2
60	1
61	1
62	4
63	4
64	2
65	3
66	3
67	3
68	2
69	2
70	1
71	1
72	4
73	4
74	2
75	2
76	2
77	3
78	2
79	2
80	1
81	1
82	3
83	4
84	2
85	3
86	3
87	2
88	2
89	2
90	1
91	1
92	2
93	3
94	3
95	2
96	3
97	3
98	2
99	2
100	1
101	1
102	1
103	1
104	1
105	1
106	1
107	1