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) |
|---|---|
| 1 | 21 |
| 2 | 225 |
| 3 | 4033 |
| 4 | 57249 |
| 5 | 844553 |
| 6 | 12323337 |
| 7 | 180983751 |
| 8 | 2656615237 |
| 9 | 38958452805 |
| 10 | 571246999054 |
| 11 | 8377493560653 |
| 12 | 122869945358060 |
| 13 | 1802067766211909 |
| 14 | 26429403407143030 |
| 15 | 387617125521945071 |
| 16 | 5684873531729895393 |