A356157 - cp's OEIS frontend

A356157 The nearest common ancestor of sigma(n) and gcd(n, sigma(n)) in the Doudna tree (A005940).

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

[1, 1, 1, 1, 1, 6, 1, 1, 1, 2, 1, 2, 1, 2, 3, 1, 1, 3, 1, 2, 1, 2, 1, 6, 1, 2, 1, 28, 1, 2, 1, 1, 3, 2, 1, 1, 1, 2, 1, 3, 1, 6, 1, 2, 3, 2, 1, 2, 1, 1, 2, 2, 1, 6, 1, 2, 1, 2, 1, 3, 1, 2, 1, 1, 1, 2, 1, 2, 3, 2, 1, 3, 1, 2, 1, 2, 1, 3, 1, 2, 1, 2, 1, 28, 1, 2, 3, 2, 1, 2, 7, 2, 1, 2, 3, 3, 1, 1, 3, 1, 1, 2, 1, 2, 3]

cp's OEIS Frontend

A356157 The nearest common ancestor of sigma(n) and gcd(n, sigma(n)) in the Doudna tree (A005940).

Table of values

List of values

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

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

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