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 | 28 |
| 2 | 406 |
| 3 | 4088 |
| 4 | 32249 |
| 5 | 212772 |
| 6 | 1222438 |
| 7 | 6283400 |
| 8 | 29454432 |
| 9 | 127721972 |
| 10 | 517920340 |
| 11 | 1980864312 |
| 12 | 7194850761 |
| 13 | 24957519216 |
| 14 | 83064794746 |
| 15 | 266299577040 |
| 16 | 825106028411 |
| 17 | 2477872472348 |
| 18 | 7230302637376 |
| 19 | 20543975496576 |
| 20 | 56949757063171 |
| 21 | 154281017250160 |
| 22 | 409072030569524 |