A058005 - cp's OEIS frontend

A058005 a(n) = gcd(2n, binomial(2n, n)).

n	a(n)
1	2
2	2
3	2
4	2
5	2
6	12
7	2
8	2
9	2
10	4
11	2
12	4
13	2
14	4
15	30
16	2
17	2
18	12
19	2
20	20
21	6
22	4
23	2
24	12
25	2
26	4
27	2
28	56
29	2
30	4
31	2
32	2
33	6
34	4
35	14
36	4
37	2
38	4
39	2
40	20
41	2
42	84
43	2
44	8
45	90
46	4
47	2
48	12
49	2
50	4
51	6
52	8
53	2
54	12
55	2
56	8
57	6
58	4
59	2
60	24
61	2
62	4
63	6
64	2
65	10
66	132
67	2
68	4
69	6
70	20
71	2
72	36
73	2
74	4
75	30
76	8
77	154
78	12
79	2
80	20
81	2
82	4
83	2
84	56
85	10
86	4
87	6
88	88
89	2
90	20

[2, 2, 2, 2, 2, 12, 2, 2, 2, 4, 2, 4, 2, 4, 30, 2, 2, 12, 2, 20, 6, 4, 2, 12, 2, 4, 2, 56, 2, 4, 2, 2, 6, 4, 14, 4, 2, 4, 2, 20, 2, 84, 2, 8, 90, 4, 2, 12, 2, 4, 6, 8, 2, 12, 2, 8, 6, 4, 2, 24, 2, 4, 6, 2, 10, 132, 2, 4, 6, 20, 2, 36, 2, 4, 30, 8, 154, 12, 2, 20, 2, 4, 2, 56, 10, 4, 6, 88, 2, 20]

cp's OEIS Frontend

A058005 a(n) = gcd(2n, binomial(2n, n)).

Table of values

List of values

n	a(n)
1	2
2	2
3	2
4	2
5	2
6	12
7	2
8	2
9	2
10	4
11	2
12	4
13	2
14	4
15	30
16	2
17	2
18	12
19	2
20	20
21	6
22	4
23	2
24	12
25	2
26	4
27	2
28	56
29	2
30	4
31	2
32	2
33	6
34	4
35	14
36	4
37	2
38	4
39	2
40	20
41	2
42	84
43	2
44	8
45	90
46	4
47	2
48	12
49	2
50	4
51	6
52	8
53	2
54	12
55	2
56	8
57	6
58	4
59	2
60	24
61	2
62	4
63	6
64	2
65	10
66	132
67	2
68	4
69	6
70	20
71	2
72	36
73	2
74	4
75	30
76	8
77	154
78	12
79	2
80	20
81	2
82	4
83	2
84	56
85	10
86	4
87	6
88	88
89	2
90	20

n	a(n)
1	2
2	2
3	2
4	2
5	2
6	12
7	2
8	2
9	2
10	4
11	2
12	4
13	2
14	4
15	30
16	2
17	2
18	12
19	2
20	20
21	6
22	4
23	2
24	12
25	2
26	4
27	2
28	56
29	2
30	4
31	2
32	2
33	6
34	4
35	14
36	4
37	2
38	4
39	2
40	20
41	2
42	84
43	2
44	8
45	90
46	4
47	2
48	12
49	2
50	4
51	6
52	8
53	2
54	12
55	2
56	8
57	6
58	4
59	2
60	24
61	2
62	4
63	6
64	2
65	10
66	132
67	2
68	4
69	6
70	20
71	2
72	36
73	2
74	4
75	30
76	8
77	154
78	12
79	2
80	20
81	2
82	4
83	2
84	56
85	10
86	4
87	6
88	88
89	2
90	20

cp's OEIS Frontend

A058005 a(n) = gcd(2*n, binomial(2*n, n)).

Table of values

List of values

A058005 a(n) = gcd(2n, binomial(2n, n)).

n	a(n)
1	2
2	2
3	2
4	2
5	2
6	12
7	2
8	2
9	2
10	4
11	2
12	4
13	2
14	4
15	30
16	2
17	2
18	12
19	2
20	20
21	6
22	4
23	2
24	12
25	2
26	4
27	2
28	56
29	2
30	4
31	2
32	2
33	6
34	4
35	14
36	4
37	2
38	4
39	2
40	20
41	2
42	84
43	2
44	8
45	90
46	4
47	2
48	12
49	2
50	4
51	6
52	8
53	2
54	12
55	2
56	8
57	6
58	4
59	2
60	24
61	2
62	4
63	6
64	2
65	10
66	132
67	2
68	4
69	6
70	20
71	2
72	36
73	2
74	4
75	30
76	8
77	154
78	12
79	2
80	20
81	2
82	4
83	2
84	56
85	10
86	4
87	6
88	88
89	2
90	20