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 | 5 |
| 2 | 41 |
| 3 | 365 |
| 4 | 3281 |
| 5 | 29525 |
| 6 | 265721 |
| 7 | 2391485 |
| 8 | 21523361 |
| 9 | 193710245 |
| 10 | 1743392201 |
| 11 | 15690529805 |
| 12 | 141214768241 |
| 13 | 1270932914165 |
| 14 | 11438396227481 |
| 15 | 102945566047325 |
| 16 | 926510094425921 |
| 17 | 8338590849833285 |
| 18 | 75047317648499561 |
| 19 | 675425858836496045 |
| 20 | 6078832729528464401 |