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 | 9 |
| 2 | 10 |
| 3 | 19 |
| 4 | 181 |
| 5 | 6897 |
| 6 | 62254 |
| 7 | 69151 |
| 8 | 131405 |
| 9 | 1251796 |
| 10 | 47699653 |
| 11 | 430548673 |
| 12 | 478248326 |
| 13 | 908796999 |
| 14 | 8657421317 |
| 15 | 329890807045 |
| 16 | 2977674684722 |
| 17 | 3307565491767 |
| 18 | 6285240176489 |
| 19 | 59874727080168 |
| 20 | 2281524869222873 |
| 21 | 20593598550086025 |
| 22 | 22875123419308898 |