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 | 3 |
| 3 | 14 |
| 4 | 83 |
| 5 | 570 |
| 6 | 4318 |
| 7 | 35068 |
| 8 | 299907 |
| 9 | 2668994 |
| 10 | 24513578 |
| 11 | 230981316 |
| 12 | 2222973742 |
| 13 | 21777680644 |
| 14 | 216603095388 |
| 15 | 2182653550712 |
| 16 | 22245324259811 |
| 17 | 228995136248850 |
| 18 | 2378208988952434 |
| 19 | 24893925007653748 |
| 20 | 262424206657706682 |
| 21 | 2784074166633171596 |
| 22 | 29707452318776988260 |
| 23 | 318664451642694840264 |