A056239 - cp's OEIS frontend

A056239 If n = Product_{k >= 1} (p_k)^(c_k) where p_k is k-th prime and c_k >= 0 then a(n) = Sum_{k >= 1} k*c_k.

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

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

cp's OEIS Frontend

A056239 If n = Product_{k >= 1} (p_k)^(c_k) where p_k is k-th prime and c_k >= 0 then a(n) = Sum_{k >= 1} k*c_k.

Table of values

List of values

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

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

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