A055515 - cp's OEIS frontend

A055515 a(n) = (2^n - 1)/product(2^p - 1) where the product is over all distinct primes p that divide n.

n	a(n)
1	1
2	1
3	1
4	5
5	1
6	3
7	1
8	85
9	73
10	11
11	1
12	195
13	1
14	43
15	151
16	21845
17	1
18	12483
19	1
20	11275
21	2359
22	683
23	1
24	798915
25	1082401
26	2731
27	19173961
28	704555
29	1
30	1649373
31	1
32	1431655765
33	599479
34	43691
35	8727391
36	3272356035
37	1
38	174763
39	9588151
40	11822705675
41	1
42	1649061309
43	1

[1, 1, 1, 5, 1, 3, 1, 85, 73, 11, 1, 195, 1, 43, 151, 21845, 1, 12483, 1, 11275, 2359, 683, 1, 798915, 1082401, 2731, 19173961, 704555, 1, 1649373, 1, 1431655765, 599479, 43691, 8727391, 3272356035, 1, 174763, 9588151, 11822705675, 1, 1649061309, 1]

cp's OEIS Frontend

A055515 a(n) = (2^n - 1)/product(2^p - 1) where the product is over all distinct primes p that divide n.

Table of values

List of values