A058268 - cp's OEIS frontend

A058268 An approximation to sigma_{1/2}(n): ceiling( sum_{d|n} sqrt(d) ).

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

[1, 3, 3, 5, 4, 7, 4, 8, 6, 8, 5, 13, 5, 9, 9, 12, 6, 14, 6, 15, 10, 11, 6, 20, 9, 12, 11, 17, 7, 22, 7, 17, 12, 13, 12, 26, 8, 13, 13, 24, 8, 25, 8, 20, 19, 14, 8, 31, 11, 20, 14, 21, 9, 27, 14, 27, 15, 16, 9, 40, 9, 16, 21, 25, 15, 29, 10, 23, 16, 29, 10, 42]

cp's OEIS Frontend

A058268 An approximation to sigma_{1/2}(n): ceiling( sum_{d|n} sqrt(d) ).

Table of values

List of values

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

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

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