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.

A056681 Numbers k such that 40*R_k + 1 is prime, where R_k = 11...1 is the repunit (A002275) of length k.

Table of values

n a(n)
1 1
2 3
3 10
4 27
5 54
6 93
7 474
8 2079
9 4834
10 5844
11 12337
12 20193
13 49528
14 56988
15 71545
16 77308

List of values

[1, 3, 10, 27, 54, 93, 474, 2079, 4834, 5844, 12337, 20193, 49528, 56988, 71545, 77308]