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 | 21 |
| 2 | 377 |
| 3 | 6765 |
| 4 | 121393 |
| 5 | 2178309 |
| 6 | 39088169 |
| 7 | 701408733 |
| 8 | 12586269025 |
| 9 | 225851433717 |
| 10 | 4052739537881 |
| 11 | 72723460248141 |
| 12 | 1304969544928657 |
| 13 | 23416728348467685 |
| 14 | 420196140727489673 |
| 15 | 7540113804746346429 |
| 16 | 135301852344706746049 |
| 17 | 2427893228399975082453 |