A071416 - cp's OEIS frontend

A071416 a(n) = gcd(n, binomial(2*n, n)).

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

[1, 2, 1, 2, 1, 6, 1, 2, 1, 2, 1, 4, 1, 2, 15, 2, 1, 6, 1, 20, 3, 2, 1, 12, 1, 2, 1, 28, 1, 2, 1, 2, 3, 2, 7, 4, 1, 2, 1, 20, 1, 42, 1, 4, 45, 2, 1, 12, 1, 2, 3, 4, 1, 6, 1, 8, 3, 2, 1, 12, 1, 2, 3, 2, 5, 66, 1, 4, 3, 10, 1, 36, 1, 2, 15, 4, 77, 6, 1, 20, 1, 2, 1, 28, 5, 2, 3, 88, 1, 10, 91, 4, 1, 2, 5]

cp's OEIS Frontend

A071416 a(n) = gcd(n, binomial(2*n, n)).

Table of values

List of values

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

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

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