A204845 - cp's OEIS frontend

A204845 Irregular triangle read by rows in which row n lists primitive prime factors of the repunit (10^n - 1)/9 (A002275(n)).

n	a(n)
1	1
2	11
3	3
4	37
5	101
6	41
7	271
8	7
9	13
10	239
11	4649
12	73
13	137
14	333667
15	9091
16	21649
17	513239
18	9901
19	53
20	79
21	265371653
22	909091
23	31
24	2906161
25	17
26	5882353
27	2071723
28	5363222357
29	19
30	52579
31	1111111111111111111
32	3541
33	27961
34	43
35	1933
36	10838689
37	23
38	4093
39	8779
40	11111111111111111111111

[1, 11, 3, 37, 101, 41, 271, 7, 13, 239, 4649, 73, 137, 333667, 9091, 21649, 513239, 9901, 53, 79, 265371653, 909091, 31, 2906161, 17, 5882353, 2071723, 5363222357, 19, 52579, 1111111111111111111, 3541, 27961, 43, 1933, 10838689, 23, 4093, 8779, 11111111111111111111111]

cp's OEIS Frontend

A204845 Irregular triangle read by rows in which row n lists primitive prime factors of the repunit (10^n - 1)/9 (A002275(n)).

Table of values

List of values