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 | 3 |
| 2 | 15 |
| 3 | 7 |
| 4 | 341 |
| 5 | 819 |
| 6 | 9709 |
| 7 | 2047 |
| 8 | 475107 |
| 9 | 31 |
| 10 | 3233097 |
| 11 | 5461 |
| 12 | 8388607 |
| 13 | 3556769739 |
| 14 | 31675383749 |
| 15 | 65498251203 |
| 16 | 575525617597 |
| 17 | 34359738367 |
| 18 | 549755813887 |
| 19 | 182518930210733 |
| 20 | 2047 |
| 21 | 37905296863701641 |
| 22 | 2251799813685247 |
| 23 | 963770320257286037 |
| 24 | 127 |
| 25 | 4833046947311902523261 |
| 26 | 82051117639860085587829 |
| 27 | 2814530423790308547362667 |