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 | 3 |
| 2 | 8 |
| 3 | 21 |
| 4 | 58 |
| 5 | 160 |
| 6 | 441 |
| 7 | 1217 |
| 8 | 3357 |
| 9 | 9261 |
| 10 | 25550 |
| 11 | 70492 |
| 12 | 194481 |
| 13 | 536558 |
| 14 | 1480324 |
| 15 | 4084101 |
| 16 | 11267725 |
| 17 | 31086799 |
| 18 | 85766121 |
| 19 | 236622225 |
| 20 | 652822777 |
| 21 | 1801088541 |
| 22 | 4969066720 |
| 23 | 13709278307 |
| 24 | 37822859361 |
| 25 | 104350401111 |
| 26 | 287894844440 |
| 27 | 794280046581 |
| 28 | 2191358423329 |