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 | 6 |
| 2 | 21 |
| 3 | 76 |
| 4 | 235 |
| 5 | 738 |
| 6 | 2177 |
| 7 | 6424 |
| 8 | 18423 |
| 9 | 52590 |
| 10 | 147917 |
| 11 | 413796 |
| 12 | 1147523 |
| 13 | 3166842 |
| 14 | 8689305 |
| 15 | 23745584 |
| 16 | 64621199 |
| 17 | 175277574 |
| 18 | 473909989 |
| 19 | 1277864060 |
| 20 | 3436938267 |
| 21 | 9223203858 |
| 22 | 24699503281 |
| 23 | 66020102472 |
| 24 | 176160084775 |
| 25 | 469293598878 |