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 | 7 |
| 1 | 49 |
| 2 | 385 |
| 3 | 3073 |
| 4 | 24577 |
| 5 | 196609 |
| 6 | 1572865 |
| 7 | 12582913 |
| 8 | 100663297 |
| 9 | 805306369 |
| 10 | 6442450945 |
| 11 | 51539607553 |
| 12 | 412316860417 |
| 13 | 3298534883329 |
| 14 | 26388279066625 |
| 15 | 211106232532993 |
| 16 | 1688849860263937 |
| 17 | 13510798882111489 |
| 18 | 108086391056891905 |