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 | 2 |
| 2 | 6 |
| 3 | 17 |
| 4 | 49 |
| 5 | 141 |
| 6 | 406 |
| 7 | 1169 |
| 8 | 3366 |
| 9 | 9692 |
| 10 | 27907 |
| 11 | 80355 |
| 12 | 231373 |
| 13 | 666212 |
| 14 | 1918281 |
| 15 | 5523470 |
| 16 | 15904198 |
| 17 | 45794313 |
| 18 | 131859469 |
| 19 | 379674209 |
| 20 | 1093228314 |
| 21 | 3147825473 |
| 22 | 9063802210 |
| 23 | 26098178316 |
| 24 | 75146709475 |
| 25 | 216376326215 |
| 26 | 623030800329 |