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 | 9 |
| 2 | 17 |
| 3 | 91 |
| 4 | 321 |
| 5 | 1341 |
| 6 | 5269 |
| 7 | 21379 |
| 8 | 85633 |
| 9 | 344955 |
| 10 | 1386679 |
| 11 | 5579199 |
| 12 | 22440525 |
| 13 | 90271591 |
| 14 | 363117835 |
| 15 | 1460674773 |
| 16 | 5875648527 |
| 17 | 23635221447 |
| 18 | 95074256043 |
| 19 | 382442764281 |
| 20 | 1538402105163 |
| 21 | 6188327969265 |
| 22 | 24892972759953 |
| 23 | 100133687989929 |