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 | 3 |
| 2 | 23 |
| 3 | 198 |
| 4 | 1795 |
| 5 | 16758 |
| 6 | 159446 |
| 7 | 1537308 |
| 8 | 14967843 |
| 9 | 146833830 |
| 10 | 1449054178 |
| 11 | 14369723316 |
| 12 | 143072565454 |
| 13 | 1429331585724 |
| 14 | 14320668653580 |
| 15 | 143838879376248 |
| 16 | 1447883909314851 |
| 17 | 14602334949928710 |
| 18 | 147518977428892010 |
| 19 | 1492559101878005700 |
| 20 | 15121898521185194970 |