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 | 3 |
| 2 | 6 |
| 3 | 15 |
| 4 | 45 |
| 5 | 69 |
| 6 | 381 |
| 7 | 387 |
| 8 | 1890 |
| 9 | 3393 |
| 10 | 14907 |
| 11 | 17799 |
| 12 | 139518 |
| 13 | 133101 |
| 14 | 798129 |
| 15 | 1804431 |
| 16 | 5452434 |
| 17 | 8072529 |
| 18 | 64596051 |
| 19 | 64573623 |
| 20 | 437717394 |
| 21 | 872156889 |
| 22 | 3138141621 |
| 23 | 4279259571 |
| 24 | 35361942282 |
| 25 | 42364514331 |