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 | 4 |
| 3 | 10 |
| 4 | 30 |
| 5 | 103 |
| 6 | 384 |
| 7 | 1508 |
| 8 | 6126 |
| 9 | 25513 |
| 10 | 108278 |
| 11 | 466523 |
| 12 | 2034981 |
| 13 | 8968746 |
| 14 | 39875940 |
| 15 | 138760603 |
| 16 | 178636543 |
| 17 | 3026583484 |
| 18 | 16028356176 |
| 19 | 75647274620 |
| 20 | 350111055991 |
| 21 | 1618175863400 |
| 22 | 7495933933620 |
| 23 | 34821723061950 |