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 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 7 |
| 5 | 13 |
| 6 | 20 |
| 7 | 38 |
| 8 | 69 |
| 9 | 129 |
| 10 | 222 |
| 11 | 407 |
| 12 | 726 |
| 13 | 1313 |
| 14 | 2318 |
| 15 | 4146 |
| 16 | 7432 |
| 17 | 13296 |
| 18 | 23759 |
| 19 | 42458 |
| 20 | 75714 |