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.

A007647 Numbers k such that k*10^k + 1 is prime.

Table of values

n a(n)
1 1
2 3
3 9
4 21
5 363
6 2161
7 4839
8 49521
9 105994
10 207777

List of values

[1, 3, 9, 21, 363, 2161, 4839, 49521, 105994, 207777]