A058266 - cp's OEIS frontend

A058266 An approximation to sigma_{1/2}(n): floor( sum_{ d divides n } sqrt(d) ).

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

[1, 2, 2, 4, 3, 6, 3, 7, 5, 7, 4, 12, 4, 8, 8, 11, 5, 13, 5, 14, 9, 10, 5, 19, 8, 11, 10, 16, 6, 21, 6, 16, 11, 12, 11, 25, 7, 12, 12, 23, 7, 24, 7, 19, 18, 13, 7, 30, 10, 19, 13, 20, 8, 26, 13, 26, 14, 15, 8, 39, 8, 15, 20, 24, 14, 28, 9, 22, 15, 28, 9, 41, 9]

cp's OEIS Frontend

A058266 An approximation to sigma_{1/2}(n): floor( sum_{ d divides n } sqrt(d) ).

Table of values

List of values

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

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

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