A080405 - cp's OEIS frontend

A080405 Number of distinct primes dividing n-th Catalan number.

n	a(n)
0	0
1	0
2	1
3	1
4	2
5	3
6	3
7	3
8	4
9	4
10	4
11	5
12	5
13	5
14	6
15	6
16	7
17	8
18	8
19	9
20	9
21	9
22	9
23	9
24	9
25	9
26	9
27	10
28	11
29	11
30	11
31	11
32	12
33	13
34	13
35	13
36	13
37	13
38	13
39	14
40	14
41	15
42	15
43	15
44	16
45	16
46	16
47	17
48	17
49	17
50	17
51	17
52	17
53	19
54	18
55	18
56	18
57	18
58	19
59	19
60	20
61	20
62	20
63	20
64	21
65	22
66	22
67	23
68	22
69	22
70	22
71	23
72	23
73	23
74	24
75	24
76	25
77	25

[0, 0, 1, 1, 2, 3, 3, 3, 4, 4, 4, 5, 5, 5, 6, 6, 7, 8, 8, 9, 9, 9, 9, 9, 9, 9, 9, 10, 11, 11, 11, 11, 12, 13, 13, 13, 13, 13, 13, 14, 14, 15, 15, 15, 16, 16, 16, 17, 17, 17, 17, 17, 17, 19, 18, 18, 18, 18, 19, 19, 20, 20, 20, 20, 21, 22, 22, 23, 22, 22, 22, 23, 23, 23, 24, 24, 25, 25]

cp's OEIS Frontend

A080405 Number of distinct primes dividing n-th Catalan number.

Table of values

List of values

n	a(n)
0	0
1	0
2	1
3	1
4	2
5	3
6	3
7	3
8	4
9	4
10	4
11	5
12	5
13	5
14	6
15	6
16	7
17	8
18	8
19	9
20	9
21	9
22	9
23	9
24	9
25	9
26	9
27	10
28	11
29	11
30	11
31	11
32	12
33	13
34	13
35	13
36	13
37	13
38	13
39	14
40	14
41	15
42	15
43	15
44	16
45	16
46	16
47	17
48	17
49	17
50	17
51	17
52	17
53	19
54	18
55	18
56	18
57	18
58	19
59	19
60	20
61	20
62	20
63	20
64	21
65	22
66	22
67	23
68	22
69	22
70	22
71	23
72	23
73	23
74	24
75	24
76	25
77	25

n	a(n)
0	0
1	0
2	1
3	1
4	2
5	3
6	3
7	3
8	4
9	4
10	4
11	5
12	5
13	5
14	6
15	6
16	7
17	8
18	8
19	9
20	9
21	9
22	9
23	9
24	9
25	9
26	9
27	10
28	11
29	11
30	11
31	11
32	12
33	13
34	13
35	13
36	13
37	13
38	13
39	14
40	14
41	15
42	15
43	15
44	16
45	16
46	16
47	17
48	17
49	17
50	17
51	17
52	17
53	19
54	18
55	18
56	18
57	18
58	19
59	19
60	20
61	20
62	20
63	20
64	21
65	22
66	22
67	23
68	22
69	22
70	22
71	23
72	23
73	23
74	24
75	24
76	25
77	25

n	a(n)
0	0
1	0
2	1
3	1
4	2
5	3
6	3
7	3
8	4
9	4
10	4
11	5
12	5
13	5
14	6
15	6
16	7
17	8
18	8
19	9
20	9
21	9
22	9
23	9
24	9
25	9
26	9
27	10
28	11
29	11
30	11
31	11
32	12
33	13
34	13
35	13
36	13
37	13
38	13
39	14
40	14
41	15
42	15
43	15
44	16
45	16
46	16
47	17
48	17
49	17
50	17
51	17
52	17
53	19
54	18
55	18
56	18
57	18
58	19
59	19
60	20
61	20
62	20
63	20
64	21
65	22
66	22
67	23
68	22
69	22
70	22
71	23
72	23
73	23
74	24
75	24
76	25
77	25