A264970 - cp's OEIS frontend

A264970 If A262686(n) = 0, a(n) = 0, otherwise a(n) = 1 + a(A262686(n)), where A262686(n) = largest number k such that k - d(k) = n, or 0 if no such number exists, and d(n) = the number of divisors of n (A000005).

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

[12, 2, 11, 2, 1, 1, 10, 0, 0, 3, 2, 2, 9, 0, 1, 5, 1, 4, 8, 0, 0, 3, 7, 2, 0, 0, 2, 1, 0, 1, 6, 6, 1, 0, 5, 5, 0, 0, 6, 4, 0, 1, 4, 0, 1, 3, 3, 2, 5, 0, 0, 1, 0, 2, 2, 0, 0, 1, 1, 4, 4, 3, 3, 0, 0, 2, 0, 0, 0, 1, 2, 3, 3, 2, 0, 0, 2, 1, 4, 0, 1, 1, 3, 3, 2, 0, 2, 2, 0, 4, 3, 1, 1, 3, 2, 5, 1, 4, 0, 2, 0]

cp's OEIS Frontend

A264970 If A262686(n) = 0, a(n) = 0, otherwise a(n) = 1 + a(A262686(n)), where A262686(n) = largest number k such that k - d(k) = n, or 0 if no such number exists, and d(n) = the number of divisors of n (A000005).

Table of values

List of values

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

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

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