A283625 - cp's OEIS frontend

A283625 Smallest k such that 2n - 1 divides sigma(k^2), or 0 if no such k exists.

n	a(n)
1	1
2	7
3	121
4	2
5	91
6	9
7	3
8	847
9	12667700813876161
10	7
11	14
12	32
13	116281
14	1729
15	343
16	4
17	63
18	242
19	47
20	21
21	1369
22	79
23	11011
24	2048
25	22
26	88673905697133127
27	4826809
28	961
29	7
30	4782969
31	13
32	182
33	363
34	29
35	224
36	25
37	16
38	813967
39	18
40	23
41	53599
42	3486784401
43	1532791798479015481
44	4459

[1, 7, 121, 2, 91, 9, 3, 847, 12667700813876161, 7, 14, 32, 116281, 1729, 343, 4, 63, 242, 47, 21, 1369, 79, 11011, 2048, 22, 88673905697133127, 4826809, 961, 7, 4782969, 13, 182, 363, 29, 224, 25, 16, 813967, 18, 23, 53599, 3486784401, 1532791798479015481, 4459]

cp's OEIS Frontend

A283625 Smallest k such that 2n - 1 divides sigma(k^2), or 0 if no such k exists.

Table of values

List of values