A344672 - cp's OEIS frontend

A344672 a(n) = Sum_{primes p <=n} phi(floor(n/p)).

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

[0, 1, 2, 2, 3, 4, 5, 5, 6, 8, 9, 7, 8, 12, 15, 13, 14, 14, 15, 13, 18, 24, 25, 17, 19, 27, 29, 23, 24, 22, 23, 23, 30, 38, 44, 28, 29, 41, 50, 38, 39, 35, 36, 34, 38, 50, 51, 37, 41, 51, 60, 52, 53, 49, 57, 49, 62, 78, 79, 43, 44, 66, 72, 58, 68, 68, 69, 65, 78, 78]

cp's OEIS Frontend

A344672 a(n) = Sum_{primes p <=n} phi(floor(n/p)).

Table of values

List of values

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

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

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