A071391 - cp's OEIS frontend

A071391 Least number m such that sigma(m) + phi(m) = n or 0 if no such number exists.

n	a(n)
1	0
2	1
3	0
4	2
5	0
6	3
7	0
8	0
9	4
10	5
11	0
12	0
13	0
14	6
15	0
16	0
17	0
18	0
19	8
20	0
21	0
22	10
23	0
24	0
25	0
26	13
27	0
28	0
29	0
30	14
31	0
32	12
33	0
34	17
35	0
36	0
37	0
38	19
39	16
40	0
41	0
42	0
43	0
44	21
45	18
46	22
47	0
48	0
49	0
50	20
51	25
52	0
53	0
54	26
55	0
56	0
57	0
58	27
59	0
60	0
61	0
62	31
63	0
64	0
65	0
66	0
67	0
68	24
69	0
70	34
71	0
72	35
73	0
74	37
75	0
76	0
77	0
78	38
79	32
80	30
81	0
82	41
83	0
84	0
85	0
86	43
87	0
88	0
89	0
90	0
91	0
92	0

[0, 1, 0, 2, 0, 3, 0, 0, 4, 5, 0, 0, 0, 6, 0, 0, 0, 0, 8, 0, 0, 10, 0, 0, 0, 13, 0, 0, 0, 14, 0, 12, 0, 17, 0, 0, 0, 19, 16, 0, 0, 0, 0, 21, 18, 22, 0, 0, 0, 20, 25, 0, 0, 26, 0, 0, 0, 27, 0, 0, 0, 31, 0, 0, 0, 0, 0, 24, 0, 34, 0, 35, 0, 37, 0, 0, 0, 38, 32, 30, 0, 41, 0, 0, 0, 43, 0, 0, 0, 0, 0, 0]

cp's OEIS Frontend

A071391 Least number m such that sigma(m) + phi(m) = n or 0 if no such number exists.

Table of values

List of values

n	a(n)
1	0
2	1
3	0
4	2
5	0
6	3
7	0
8	0
9	4
10	5
11	0
12	0
13	0
14	6
15	0
16	0
17	0
18	0
19	8
20	0
21	0
22	10
23	0
24	0
25	0
26	13
27	0
28	0
29	0
30	14
31	0
32	12
33	0
34	17
35	0
36	0
37	0
38	19
39	16
40	0
41	0
42	0
43	0
44	21
45	18
46	22
47	0
48	0
49	0
50	20
51	25
52	0
53	0
54	26
55	0
56	0
57	0
58	27
59	0
60	0
61	0
62	31
63	0
64	0
65	0
66	0
67	0
68	24
69	0
70	34
71	0
72	35
73	0
74	37
75	0
76	0
77	0
78	38
79	32
80	30
81	0
82	41
83	0
84	0
85	0
86	43
87	0
88	0
89	0
90	0
91	0
92	0

n	a(n)
1	0
2	1
3	0
4	2
5	0
6	3
7	0
8	0
9	4
10	5
11	0
12	0
13	0
14	6
15	0
16	0
17	0
18	0
19	8
20	0
21	0
22	10
23	0
24	0
25	0
26	13
27	0
28	0
29	0
30	14
31	0
32	12
33	0
34	17
35	0
36	0
37	0
38	19
39	16
40	0
41	0
42	0
43	0
44	21
45	18
46	22
47	0
48	0
49	0
50	20
51	25
52	0
53	0
54	26
55	0
56	0
57	0
58	27
59	0
60	0
61	0
62	31
63	0
64	0
65	0
66	0
67	0
68	24
69	0
70	34
71	0
72	35
73	0
74	37
75	0
76	0
77	0
78	38
79	32
80	30
81	0
82	41
83	0
84	0
85	0
86	43
87	0
88	0
89	0
90	0
91	0
92	0

n	a(n)
1	0
2	1
3	0
4	2
5	0
6	3
7	0
8	0
9	4
10	5
11	0
12	0
13	0
14	6
15	0
16	0
17	0
18	0
19	8
20	0
21	0
22	10
23	0
24	0
25	0
26	13
27	0
28	0
29	0
30	14
31	0
32	12
33	0
34	17
35	0
36	0
37	0
38	19
39	16
40	0
41	0
42	0
43	0
44	21
45	18
46	22
47	0
48	0
49	0
50	20
51	25
52	0
53	0
54	26
55	0
56	0
57	0
58	27
59	0
60	0
61	0
62	31
63	0
64	0
65	0
66	0
67	0
68	24
69	0
70	34
71	0
72	35
73	0
74	37
75	0
76	0
77	0
78	38
79	32
80	30
81	0
82	41
83	0
84	0
85	0
86	43
87	0
88	0
89	0
90	0
91	0
92	0