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 | 12 |
| 1 | 45 |
| 2 | 177 |
| 3 | 705 |
| 4 | 2817 |
| 5 | 11265 |
| 6 | 45057 |
| 7 | 180225 |
| 8 | 720897 |
| 9 | 2883585 |
| 10 | 11534337 |
| 11 | 46137345 |
| 12 | 184549377 |
| 13 | 738197505 |
| 14 | 2952790017 |
| 15 | 11811160065 |
| 16 | 47244640257 |
| 17 | 188978561025 |
| 18 | 755914244097 |
| 19 | 3023656976385 |
| 20 | 12094627905537 |
| 21 | 48378511622145 |
| 22 | 193514046488577 |
| 23 | 774056185954305 |
| 24 | 3096224743817217 |