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 | 1 |
| 2 | 9 |
| 3 | 41 |
| 4 | 79 |
| 5 | 351 |
| 6 | 1559 |
| 7 | 3001 |
| 8 | 13329 |
| 9 | 59201 |
| 10 | 113959 |
| 11 | 506151 |
| 12 | 2248079 |
| 13 | 4327441 |
| 14 | 19220409 |
| 15 | 85367801 |
| 16 | 164328799 |
| 17 | 729869391 |
| 18 | 3241728359 |
| 19 | 6240166921 |
| 20 | 27715816449 |
| 21 | 123100309841 |
| 22 | 236962014199 |
| 23 | 1052471155671 |
| 24 | 4674570045599 |
| 25 | 8998316372641 |
| 26 | 39966188099049 |
| 27 | 177510561422921 |