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 | 7 |
| 3 | 13 |
| 4 | 57 |
| 5 | 253 |
| 6 | 487 |
| 7 | 2163 |
| 8 | 9607 |
| 9 | 18493 |
| 10 | 82137 |
| 11 | 364813 |
| 12 | 702247 |
| 13 | 3119043 |
| 14 | 13853287 |
| 15 | 26666893 |
| 16 | 118441497 |
| 17 | 526060093 |
| 18 | 1012639687 |
| 19 | 4497657843 |
| 20 | 19976430247 |
| 21 | 38453641213 |
| 22 | 170792556537 |
| 23 | 758578289293 |
| 24 | 1460225726407 |
| 25 | 6485619490563 |
| 26 | 28805998562887 |
| 27 | 55450123962253 |