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 | 1 |
| 3 | 2 |
| 4 | 3 |
| 5 | 13 |
| 6 | 63 |
| 7 | 199 |
| 8 | 805 |
| 9 | 3155 |
| 10 | 12319 |
| 11 | 48070 |
| 12 | 186944 |
| 13 | 727997 |
| 14 | 2846645 |
| 15 | 11109160 |
| 16 | 43432775 |
| 17 | 169958492 |
| 18 | 665601661 |
| 19 | 2608395091 |