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 | 11 |
| 3 | 64 |
| 4 | 345 |
| 5 | 1824 |
| 6 | 9661 |
| 7 | 51284 |
| 8 | 272333 |
| 9 | 1445995 |
| 10 | 7677250 |
| 11 | 40760798 |
| 12 | 216412235 |
| 13 | 1149004281 |
| 14 | 6100444144 |
| 15 | 32389272248 |
| 16 | 171965334801 |
| 17 | 913020717480 |
| 18 | 4847528344990 |
| 19 | 25737127996244 |
| 20 | 136646907481155 |
| 21 | 725503534206186 |
| 22 | 3851937726561990 |
| 23 | 20451208781128462 |