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 | 7 |
| 3 | 29 |
| 4 | 103 |
| 5 | 405 |
| 6 | 1599 |
| 7 | 6141 |
| 8 | 23863 |
| 9 | 92773 |
| 10 | 359791 |
| 11 | 1396493 |
| 12 | 5421415 |
| 13 | 21041397 |
| 14 | 81670431 |
| 15 | 317005341 |
| 16 | 1230432919 |
| 17 | 4775854213 |
| 18 | 18537264079 |
| 19 | 71951401517 |
| 20 | 279275580103 |
| 21 | 1083993881877 |
| 22 | 4207466012031 |
| 23 | 16331061009213 |