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 | 1 |
| 2 | 5 |
| 3 | 46 |
| 4 | 689 |
| 5 | 15476 |
| 6 | 483157 |
| 7 | 19719022 |
| 8 | 1009495489 |
| 9 | 63119450152 |
| 10 | 4728073048901 |
| 11 | 417482964953594 |
| 12 | 42834647403146161 |
| 13 | 5043607239173464924 |
| 14 | 674409403861210214485 |
| 15 | 101517071981284179924526 |
| 16 | 17074451852556909059698433 |
| 17 | 3187883879639402167714593488 |
| 18 | 656838643288782957496595002117 |