A134889 - cp's OEIS frontend

A134889 a(n)=the largest sum of two nontrivial divisors of n, if any, whose product equals n; otherwise, a(n)=n.

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

[1, 2, 3, 4, 5, 5, 7, 6, 6, 7, 11, 8, 13, 9, 8, 10, 17, 11, 19, 12, 10, 13, 23, 14, 10, 15, 12, 16, 29, 17, 31, 18, 14, 19, 12, 20, 37, 21, 16, 22, 41, 23, 43, 24, 18, 25, 47, 26, 14, 27, 20, 28, 53, 29, 16, 30, 22, 31, 59, 32, 61, 33, 24, 34, 18, 35, 67, 36, 26, 37, 71, 38, 73, 39]

cp's OEIS Frontend

A134889 a(n)=the largest sum of two nontrivial divisors of n, if any, whose product equals n; otherwise, a(n)=n.

Table of values

List of values

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

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

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