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 | 2 |
| 2 | 5 |
| 3 | 14 |
| 4 | 42 |
| 5 | 132 |
| 6 | 430 |
| 7 | 1444 |
| 8 | 4984 |
| 9 | 17648 |
| 10 | 64024 |
| 11 | 237712 |
| 12 | 902416 |
| 13 | 3499680 |
| 14 | 13853424 |
| 15 | 55931168 |
| 16 | 230142848 |
| 17 | 964460288 |
| 18 | 4113656704 |
| 19 | 17846729984 |
| 20 | 78708574976 |
| 21 | 352678567424 |
| 22 | 1604739694848 |
| 23 | 7411167960576 |
| 24 | 34723660917760 |