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 | 2 |
| 2 | 5 |
| 3 | 109 |
| 4 | 257 |
| 5 | 37501 |
| 6 | 139969 |
| 7 | 3294173 |
| 8 | 167772161 |
| 9 | 3874204891 |
| 10 | 30000000001 |
| 11 | 24536803672547 |
| 12 | 17832200896513 |
| 13 | 12115004263690121 |
| 14 | 344472211592298497 |
| 15 | 12261028930664062501 |
| 16 | 221360928884514619393 |
| 17 | 6617922095090694113417 |