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 | 5 |
| 2 | 43 |
| 3 | 341 |
| 4 | 2731 |
| 5 | 21845 |
| 6 | 174763 |
| 7 | 1398101 |
| 8 | 11184811 |
| 9 | 89478485 |
| 10 | 715827883 |
| 11 | 5726623061 |
| 12 | 45812984491 |
| 13 | 366503875925 |
| 14 | 2932031007403 |
| 15 | 23456248059221 |
| 16 | 187649984473771 |
| 17 | 1501199875790165 |
| 18 | 12009599006321323 |
| 19 | 96076792050570581 |
| 20 | 768614336404564651 |
| 21 | 6148914691236517205 |