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) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 22 |
| 3 | 187 |
| 4 | 1219 |
| 5 | 7597 |
| 6 | 46117 |
| 7 | 278857 |
| 8 | 1676377 |
| 9 | 10067797 |
| 10 | 60450517 |
| 11 | 362758177 |
| 12 | 2176626817 |
| 13 | 13060193977 |
| 14 | 78363525817 |
| 15 | 470183516857 |
| 16 | 2820894903487 |
| 17 | 16926601754197 |
| 18 | 101559860054047 |
| 19 | 609359671998037 |
| 20 | 3656158318966357 |