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 | 1 |
| 1 | 5 |
| 2 | 17 |
| 3 | 54 |
| 4 | 165 |
| 5 | 482 |
| 6 | 1319 |
| 7 | 3390 |
| 8 | 8262 |
| 9 | 19250 |
| 10 | 43154 |
| 11 | 93601 |
| 12 | 197381 |
| 13 | 406200 |
| 14 | 817954 |
| 15 | 1614348 |
| 16 | 3126068 |
| 17 | 5943728 |
| 18 | 11103912 |
| 19 | 20396957 |
| 20 | 36869790 |
| 21 | 65637607 |
| 22 | 115178814 |
| 23 | 199377387 |
| 24 | 340708159 |
| 25 | 575150851 |
| 26 | 959691775 |
| 27 | 1583660542 |