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 | 11 |
| 2 | 60 |
| 3 | 328 |
| 4 | 1800 |
| 5 | 9924 |
| 6 | 54964 |
| 7 | 305680 |
| 8 | 1706256 |
| 9 | 9554620 |
| 10 | 53653996 |
| 11 | 302038488 |
| 12 | 1703995800 |
| 13 | 9631951476 |
| 14 | 54539233380 |
| 15 | 309296779296 |
| 16 | 1756495236128 |
| 17 | 9987721546860 |
| 18 | 56857004161180 |
| 19 | 324008331785320 |
| 20 | 1848182861702184 |