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 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 3 |
| 6 | 6 |
| 7 | 11 |
| 8 | 21 |
| 9 | 43 |
| 10 | 89 |
| 11 | 185 |
| 12 | 391 |
| 13 | 840 |
| 14 | 1822 |
| 15 | 3975 |
| 16 | 8727 |
| 17 | 19280 |
| 18 | 42841 |
| 19 | 95661 |
| 20 | 214490 |