A335372 - cp's OEIS frontend

A335372 a(0) = 0, a(1) = 1; for n > 1, a(n) = a(n-1) - A001065(n) if nonnegative and not already in the sequence, otherwise a(n) = a(n-1) + A001065(n), where A001065(n) is the sum of the proper divisors of n.

n	a(n)
0	0
1	1
2	2
3	3
4	6
5	5
6	11
7	10
8	17
9	13
10	21
11	20
12	4
13	5
14	15
15	24
16	9
17	8
18	29
19	28
20	50
21	39
22	25
23	26
24	62
25	56
26	40
27	27
28	55
29	54
30	12
31	13
32	44
33	59
34	79
35	66
36	121
37	120
38	98
39	81
40	31
41	30
42	84
43	83
44	43
45	76
46	102
47	101
48	177
49	169
50	126
51	105
52	151
53	150
54	216
55	199
56	135
57	112
58	80
59	81
60	189
61	188
62	154
63	113
64	176
65	157
66	235
67	234
68	292

[0, 1, 2, 3, 6, 5, 11, 10, 17, 13, 21, 20, 4, 5, 15, 24, 9, 8, 29, 28, 50, 39, 25, 26, 62, 56, 40, 27, 55, 54, 12, 13, 44, 59, 79, 66, 121, 120, 98, 81, 31, 30, 84, 83, 43, 76, 102, 101, 177, 169, 126, 105, 151, 150, 216, 199, 135, 112, 80, 81, 189, 188, 154, 113, 176, 157, 235, 234, 292]

cp's OEIS Frontend

A335372 a(0) = 0, a(1) = 1; for n > 1, a(n) = a(n-1) - A001065(n) if nonnegative and not already in the sequence, otherwise a(n) = a(n-1) + A001065(n), where A001065(n) is the sum of the proper divisors of n.

Table of values

List of values

n	a(n)
0	0
1	1
2	2
3	3
4	6
5	5
6	11
7	10
8	17
9	13
10	21
11	20
12	4
13	5
14	15
15	24
16	9
17	8
18	29
19	28
20	50
21	39
22	25
23	26
24	62
25	56
26	40
27	27
28	55
29	54
30	12
31	13
32	44
33	59
34	79
35	66
36	121
37	120
38	98
39	81
40	31
41	30
42	84
43	83
44	43
45	76
46	102
47	101
48	177
49	169
50	126
51	105
52	151
53	150
54	216
55	199
56	135
57	112
58	80
59	81
60	189
61	188
62	154
63	113
64	176
65	157
66	235
67	234
68	292

n	a(n)
0	0
1	1
2	2
3	3
4	6
5	5
6	11
7	10
8	17
9	13
10	21
11	20
12	4
13	5
14	15
15	24
16	9
17	8
18	29
19	28
20	50
21	39
22	25
23	26
24	62
25	56
26	40
27	27
28	55
29	54
30	12
31	13
32	44
33	59
34	79
35	66
36	121
37	120
38	98
39	81
40	31
41	30
42	84
43	83
44	43
45	76
46	102
47	101
48	177
49	169
50	126
51	105
52	151
53	150
54	216
55	199
56	135
57	112
58	80
59	81
60	189
61	188
62	154
63	113
64	176
65	157
66	235
67	234
68	292

n	a(n)
0	0
1	1
2	2
3	3
4	6
5	5
6	11
7	10
8	17
9	13
10	21
11	20
12	4
13	5
14	15
15	24
16	9
17	8
18	29
19	28
20	50
21	39
22	25
23	26
24	62
25	56
26	40
27	27
28	55
29	54
30	12
31	13
32	44
33	59
34	79
35	66
36	121
37	120
38	98
39	81
40	31
41	30
42	84
43	83
44	43
45	76
46	102
47	101
48	177
49	169
50	126
51	105
52	151
53	150
54	216
55	199
56	135
57	112
58	80
59	81
60	189
61	188
62	154
63	113
64	176
65	157
66	235
67	234
68	292