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.
| n | a(n) |
|---|---|
| 1 | 5 |
| 2 | 10 |
| 3 | 20 |
| 4 | 40 |
| 5 | 130 |
| 6 | 1010 |
| 7 | 13020 |
| 8 | 404040 |
| 9 | 100412130 |
| 10 | 201201142010 |
| 11 | 11244024443021020 |
| 12 | 43242234044024403133040 |
| 13 | 141203414122301104243434200224130 |