A353790 - cp's OEIS frontend

A353790 a(n) = A353749(sigma(A003961(n))), where A353749(k) = phi(k) * A064989(k), and A064989 shifts the prime factorization one step towards lower primes, while A003961 shifts the factorization one step towards higher primes.

n	a(n)
1	1
2	2
3	4
4	132
5	4
6	16
7	8
8	48
9	870
10	16
11	30
12	528
13	24
14	32
15	32
16	5390
17	24
18	1740
19	16
20	528
21	96
22	120
23	48
24	384
25	1224
26	96
27	1056
28	1056
29	16
30	128
31	306
32	7920
33	240
34	96
35	64
36	114840
37	120
38	64
39	288
40	384
41	140
42	384
43	32
44	3960
45	3480
46	192
47	144
48	21560
49	9180
50	2448
51	192
52	3168
53	96
54	4224
55	240
56	768
57	192
58	64
59	870
60	4224
61	416
62	1224
63	6960
64	1191372
65	192

[1, 2, 4, 132, 4, 16, 8, 48, 870, 16, 30, 528, 24, 32, 32, 5390, 24, 1740, 16, 528, 96, 120, 48, 384, 1224, 96, 1056, 1056, 16, 128, 306, 7920, 240, 96, 64, 114840, 120, 64, 288, 384, 140, 384, 32, 3960, 3480, 192, 144, 21560, 9180, 2448, 192, 3168, 96, 4224, 240, 768, 192, 64, 870, 4224, 416, 1224, 6960, 1191372, 192]

cp's OEIS Frontend

A353790 a(n) = A353749(sigma(A003961(n))), where A353749(k) = phi(k) * A064989(k), and A064989 shifts the prime factorization one step towards lower primes, while A003961 shifts the factorization one step towards higher primes.

Table of values

List of values