A081389 - cp's OEIS frontend

A081389 Number of non-unitary prime divisors of Catalan numbers, i.e., number of those prime factors whose exponent is greater than one.

n	a(n)
1	0
2	0
3	0
4	0
5	0
6	1
7	0
8	0
9	0
10	1
11	0
12	1
13	2
14	2
15	1
16	1
17	0
18	2
19	0
20	1
21	1
22	1
23	2
24	2
25	3
26	2
27	1
28	1
29	1
30	1
31	0
32	1
33	1
34	1
35	0
36	1
37	1
38	2
39	1
40	2
41	2
42	2
43	3
44	2
45	2
46	3
47	2
48	3
49	2
50	2
51	2
52	2
53	1
54	1
55	1
56	1
57	1
58	1
59	2
60	2
61	3
62	2
63	2
64	2
65	1
66	2
67	1
68	3
69	3
70	3
71	2
72	4
73	4
74	4
75	4
76	2
77	2
78	3
79	1
80	1
81	2
82	2
83	3
84	2
85	3
86	3
87	2
88	4
89	4
90	2
91	2
92	2
93	2
94	3
95	4
96	5
97	4
98	3
99	2
100	2
101	2
102	2
103	2
104	2
105	3

[0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 2, 2, 1, 1, 0, 2, 0, 1, 1, 1, 2, 2, 3, 2, 1, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 2, 1, 2, 2, 2, 3, 2, 2, 3, 2, 3, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 2, 2, 3, 2, 2, 2, 1, 2, 1, 3, 3, 3, 2, 4, 4, 4, 4, 2, 2, 3, 1, 1, 2, 2, 3, 2, 3, 3, 2, 4, 4, 2, 2, 2, 2, 3, 4, 5, 4, 3, 2, 2, 2, 2, 2, 2, 3]

cp's OEIS Frontend

A081389 Number of non-unitary prime divisors of Catalan numbers, i.e., number of those prime factors whose exponent is greater than one.

Table of values

List of values

n	a(n)
1	0
2	0
3	0
4	0
5	0
6	1
7	0
8	0
9	0
10	1
11	0
12	1
13	2
14	2
15	1
16	1
17	0
18	2
19	0
20	1
21	1
22	1
23	2
24	2
25	3
26	2
27	1
28	1
29	1
30	1
31	0
32	1
33	1
34	1
35	0
36	1
37	1
38	2
39	1
40	2
41	2
42	2
43	3
44	2
45	2
46	3
47	2
48	3
49	2
50	2
51	2
52	2
53	1
54	1
55	1
56	1
57	1
58	1
59	2
60	2
61	3
62	2
63	2
64	2
65	1
66	2
67	1
68	3
69	3
70	3
71	2
72	4
73	4
74	4
75	4
76	2
77	2
78	3
79	1
80	1
81	2
82	2
83	3
84	2
85	3
86	3
87	2
88	4
89	4
90	2
91	2
92	2
93	2
94	3
95	4
96	5
97	4
98	3
99	2
100	2
101	2
102	2
103	2
104	2
105	3

n	a(n)
1	0
2	0
3	0
4	0
5	0
6	1
7	0
8	0
9	0
10	1
11	0
12	1
13	2
14	2
15	1
16	1
17	0
18	2
19	0
20	1
21	1
22	1
23	2
24	2
25	3
26	2
27	1
28	1
29	1
30	1
31	0
32	1
33	1
34	1
35	0
36	1
37	1
38	2
39	1
40	2
41	2
42	2
43	3
44	2
45	2
46	3
47	2
48	3
49	2
50	2
51	2
52	2
53	1
54	1
55	1
56	1
57	1
58	1
59	2
60	2
61	3
62	2
63	2
64	2
65	1
66	2
67	1
68	3
69	3
70	3
71	2
72	4
73	4
74	4
75	4
76	2
77	2
78	3
79	1
80	1
81	2
82	2
83	3
84	2
85	3
86	3
87	2
88	4
89	4
90	2
91	2
92	2
93	2
94	3
95	4
96	5
97	4
98	3
99	2
100	2
101	2
102	2
103	2
104	2
105	3

n	a(n)
1	0
2	0
3	0
4	0
5	0
6	1
7	0
8	0
9	0
10	1
11	0
12	1
13	2
14	2
15	1
16	1
17	0
18	2
19	0
20	1
21	1
22	1
23	2
24	2
25	3
26	2
27	1
28	1
29	1
30	1
31	0
32	1
33	1
34	1
35	0
36	1
37	1
38	2
39	1
40	2
41	2
42	2
43	3
44	2
45	2
46	3
47	2
48	3
49	2
50	2
51	2
52	2
53	1
54	1
55	1
56	1
57	1
58	1
59	2
60	2
61	3
62	2
63	2
64	2
65	1
66	2
67	1
68	3
69	3
70	3
71	2
72	4
73	4
74	4
75	4
76	2
77	2
78	3
79	1
80	1
81	2
82	2
83	3
84	2
85	3
86	3
87	2
88	4
89	4
90	2
91	2
92	2
93	2
94	3
95	4
96	5
97	4
98	3
99	2
100	2
101	2
102	2
103	2
104	2
105	3