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 | 1 |
| 2 | 2 |
| 3 | 0 |
| 4 | 1 |
| 5 | 1 |
| 6 | 4 |
| 7 | 11 |
| 8 | 29 |
| 9 | 81 |
| 10 | 220 |
| 11 | 608 |
| 12 | 1676 |
| 13 | 4633 |
| 14 | 12847 |
| 15 | 35685 |
| 16 | 99367 |
| 17 | 277256 |
| 18 | 775197 |
| 19 | 2171691 |
| 20 | 6095329 |
| 21 | 17138861 |
| 22 | 48274370 |
| 23 | 136197884 |
| 24 | 384868351 |
| 25 | 1089211676 |
| 26 | 3087038820 |
| 27 | 8761410780 |
| 28 | 24898994687 |
| 29 | 70850054269 |
| 30 | 201848300443 |
| 31 | 575723018363 |
| 32 | 1643931888516 |