A349754 - cp's OEIS frontend

A349754 a(n) = phi(A003961(n)) - 2*phi(n), where A003961 is fully multiplicative with a(p) = nextprime(p), and phi is Euler totient function.

n	a(n)
1	-1
2	0
3	0
4	2
5	-2
6	4
7	-2
8	10
9	8
10	4
11	-8
12	16
13	-8
14	8
15	8
16	38
17	-14
18	28
19	-14
20	20
21	16
22	4
23	-16
24	56
25	2
26	8
27	64
28	36
29	-26
30	32
31	-24
32	130
33	8
34	4
35	12
36	96
37	-32
38	8
39	16
40	76
41	-38
42	56
43	-38
44	32
45	72
46	12
47	-40
48	184
49	26
50	44
51	8
52	48
53	-46
54	164
55	-8
56	132
57	16
58	4
59	-56
60	112
61	-54
62	12
63	128
64	422
65	0
66	56
67	-62
68	44
69	24
70	72
71	-68
72	312
73	-66
74	8
75	88
76	60
77	0
78	80

[-1, 0, 0, 2, -2, 4, -2, 10, 8, 4, -8, 16, -8, 8, 8, 38, -14, 28, -14, 20, 16, 4, -16, 56, 2, 8, 64, 36, -26, 32, -24, 130, 8, 4, 12, 96, -32, 8, 16, 76, -38, 56, -38, 32, 72, 12, -40, 184, 26, 44, 8, 48, -46, 164, -8, 132, 16, 4, -56, 112, -54, 12, 128, 422, 0, 56, -62, 44, 24, 72, -68, 312, -66, 8, 88, 60, 0, 80]

cp's OEIS Frontend

A349754 a(n) = phi(A003961(n)) - 2*phi(n), where A003961 is fully multiplicative with a(p) = nextprime(p), and phi is Euler totient function.

Table of values

List of values

n	a(n)
1	-1
2	0
3	0
4	2
5	-2
6	4
7	-2
8	10
9	8
10	4
11	-8
12	16
13	-8
14	8
15	8
16	38
17	-14
18	28
19	-14
20	20
21	16
22	4
23	-16
24	56
25	2
26	8
27	64
28	36
29	-26
30	32
31	-24
32	130
33	8
34	4
35	12
36	96
37	-32
38	8
39	16
40	76
41	-38
42	56
43	-38
44	32
45	72
46	12
47	-40
48	184
49	26
50	44
51	8
52	48
53	-46
54	164
55	-8
56	132
57	16
58	4
59	-56
60	112
61	-54
62	12
63	128
64	422
65	0
66	56
67	-62
68	44
69	24
70	72
71	-68
72	312
73	-66
74	8
75	88
76	60
77	0
78	80

n	a(n)
1	-1
2	0
3	0
4	2
5	-2
6	4
7	-2
8	10
9	8
10	4
11	-8
12	16
13	-8
14	8
15	8
16	38
17	-14
18	28
19	-14
20	20
21	16
22	4
23	-16
24	56
25	2
26	8
27	64
28	36
29	-26
30	32
31	-24
32	130
33	8
34	4
35	12
36	96
37	-32
38	8
39	16
40	76
41	-38
42	56
43	-38
44	32
45	72
46	12
47	-40
48	184
49	26
50	44
51	8
52	48
53	-46
54	164
55	-8
56	132
57	16
58	4
59	-56
60	112
61	-54
62	12
63	128
64	422
65	0
66	56
67	-62
68	44
69	24
70	72
71	-68
72	312
73	-66
74	8
75	88
76	60
77	0
78	80

n	a(n)
1	-1
2	0
3	0
4	2
5	-2
6	4
7	-2
8	10
9	8
10	4
11	-8
12	16
13	-8
14	8
15	8
16	38
17	-14
18	28
19	-14
20	20
21	16
22	4
23	-16
24	56
25	2
26	8
27	64
28	36
29	-26
30	32
31	-24
32	130
33	8
34	4
35	12
36	96
37	-32
38	8
39	16
40	76
41	-38
42	56
43	-38
44	32
45	72
46	12
47	-40
48	184
49	26
50	44
51	8
52	48
53	-46
54	164
55	-8
56	132
57	16
58	4
59	-56
60	112
61	-54
62	12
63	128
64	422
65	0
66	56
67	-62
68	44
69	24
70	72
71	-68
72	312
73	-66
74	8
75	88
76	60
77	0
78	80