A107759 - cp's OEIS frontend

A107759 a(n) = (+2)UnitarySigma(n): if n = Product p_i^r_i then a(n) = Product (2 + p_i^r_i).

n	a(n)
1	1
2	4
3	5
4	6
5	7
6	20
7	9
8	10
9	11
10	28
11	13
12	30
13	15
14	36
15	35
16	18
17	19
18	44
19	21
20	42
21	45
22	52
23	25
24	50
25	27
26	60
27	29
28	54
29	31
30	140
31	33
32	34
33	65
34	76
35	63
36	66
37	39
38	84
39	75
40	70
41	43
42	180
43	45
44	78
45	77
46	100
47	49
48	90
49	51
50	108
51	95
52	90
53	55
54	116
55	91

[1, 4, 5, 6, 7, 20, 9, 10, 11, 28, 13, 30, 15, 36, 35, 18, 19, 44, 21, 42, 45, 52, 25, 50, 27, 60, 29, 54, 31, 140, 33, 34, 65, 76, 63, 66, 39, 84, 75, 70, 43, 180, 45, 78, 77, 100, 49, 90, 51, 108, 95, 90, 55, 116, 91]

cp's OEIS Frontend

A107759 a(n) = (+2)UnitarySigma(n): if n = Product p_i^r_i then a(n) = Product (2 + p_i^r_i).

Table of values

List of values

n	a(n)
1	1
2	4
3	5
4	6
5	7
6	20
7	9
8	10
9	11
10	28
11	13
12	30
13	15
14	36
15	35
16	18
17	19
18	44
19	21
20	42
21	45
22	52
23	25
24	50
25	27
26	60
27	29
28	54
29	31
30	140
31	33
32	34
33	65
34	76
35	63
36	66
37	39
38	84
39	75
40	70
41	43
42	180
43	45
44	78
45	77
46	100
47	49
48	90
49	51
50	108
51	95
52	90
53	55
54	116
55	91

n	a(n)
1	1
2	4
3	5
4	6
5	7
6	20
7	9
8	10
9	11
10	28
11	13
12	30
13	15
14	36
15	35
16	18
17	19
18	44
19	21
20	42
21	45
22	52
23	25
24	50
25	27
26	60
27	29
28	54
29	31
30	140
31	33
32	34
33	65
34	76
35	63
36	66
37	39
38	84
39	75
40	70
41	43
42	180
43	45
44	78
45	77
46	100
47	49
48	90
49	51
50	108
51	95
52	90
53	55
54	116
55	91

n	a(n)
1	1
2	4
3	5
4	6
5	7
6	20
7	9
8	10
9	11
10	28
11	13
12	30
13	15
14	36
15	35
16	18
17	19
18	44
19	21
20	42
21	45
22	52
23	25
24	50
25	27
26	60
27	29
28	54
29	31
30	140
31	33
32	34
33	65
34	76
35	63
36	66
37	39
38	84
39	75
40	70
41	43
42	180
43	45
44	78
45	77
46	100
47	49
48	90
49	51
50	108
51	95
52	90
53	55
54	116
55	91