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 | 18 |
| 2 | 217 |
| 3 | 2340 |
| 4 | 24211 |
| 5 | 246078 |
| 6 | 2480437 |
| 7 | 24902280 |
| 8 | 249511591 |
| 9 | 2497558338 |
| 10 | 24987792457 |
| 11 | 249938963820 |
| 12 | 2499694822171 |
| 13 | 24998474116998 |
| 14 | 249992370597277 |
| 15 | 2499961853010960 |
| 16 | 24999809265103951 |
| 17 | 249999046325618058 |
| 18 | 2499995231628286897 |