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 | 29 |
| 2 | 267 |
| 3 | 1568 |
| 4 | 7490 |
| 5 | 32814 |
| 6 | 139638 |
| 7 | 590254 |
| 8 | 2496332 |
| 9 | 10583872 |
| 10 | 44986080 |
| 11 | 191565628 |
| 12 | 816675452 |
| 13 | 3483688120 |
| 14 | 14864259432 |
| 15 | 63428734440 |
| 16 | 270666075032 |
| 17 | 1154981259240 |
| 18 | 4928419635424 |
| 19 | 21029737949696 |
| 20 | 89733758819456 |