A317749 - cp's OEIS frontend

A317749 a(n+1) = d(n) + d(a(n)) with a(1)=1, where d(n) is the number of the divisors of n.

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

[1, 2, 4, 5, 5, 4, 7, 4, 7, 5, 6, 6, 10, 6, 8, 8, 9, 5, 8, 6, 10, 8, 8, 6, 12, 9, 7, 6, 10, 6, 12, 8, 10, 8, 8, 8, 13, 4, 7, 6, 12, 8, 12, 8, 10, 10, 8, 6, 14, 7, 8, 8, 10, 6, 12, 10, 12, 10, 8, 6, 16, 7, 6, 10, 11, 6, 12, 8, 10, 8, 12, 8, 16, 7, 6, 10, 10, 8, 12, 8, 14, 9, 7, 4, 15, 8, 8, 8, 12, 8, 16, 9, 9, 7, 6, 8, 16, 7, 8, 10]

cp's OEIS Frontend

A317749 a(n+1) = d(n) + d(a(n)) with a(1)=1, where d(n) is the number of the divisors of n.

Table of values

List of values

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

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

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