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) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 9 |
| 5 | 25 |
| 6 | 85 |
| 7 | 346 |
| 8 | 1589 |
| 9 | 7846 |
| 10 | 40567 |
| 11 | 216327 |
| 12 | 1180227 |
| 13 | 6554627 |
| 14 | 36939883 |
| 15 | 210777514 |
| 16 | 1215644593 |
| 17 | 7077255068 |
| 18 | 41546269583 |
| 19 | 245708229893 |
| 20 | 1462853468378 |
| 21 | 8761861115930 |
| 22 | 52767463557770 |