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 | 0 |
| 1 | 1 |
| 2 | 11 |
| 3 | 91 |
| 4 | 671 |
| 5 | 4651 |
| 6 | 31031 |
| 7 | 201811 |
| 8 | 1288991 |
| 9 | 8124571 |
| 10 | 50700551 |
| 11 | 313968931 |
| 12 | 1932641711 |
| 13 | 11839990891 |
| 14 | 72260648471 |
| 15 | 439667406451 |
| 16 | 2668522016831 |
| 17 | 16163719991611 |
| 18 | 97745259402791 |
| 19 | 590286253682371 |