cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A102989 Numbers n such that 4*10^n + 3*R_n + 4 is prime, where R_n = 11...1 is the repunit (A002275) of length n.

Table of values

n a(n)
1 1
2 3
3 5
4 6
5 8
6 15
7 26
8 53
9 60
10 97
11 183
12 205
13 302
14 396
15 456
16 467
17 607
18 828
19 1860
20 2743
21 4273
22 4781
23 5712
24 6038
25 6637
26 9222
27 10832
28 18865
29 25848
30 42247
31 48547
32 87565
33 95588

List of values

[1, 3, 5, 6, 8, 15, 26, 53, 60, 97, 183, 205, 302, 396, 456, 467, 607, 828, 1860, 2743, 4273, 4781, 5712, 6038, 6637, 9222, 10832, 18865, 25848, 42247, 48547, 87565, 95588]