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 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 4 |
| 6 | 8 |
| 7 | 15 |
| 8 | 37 |
| 9 | 73 |
| 10 | 182 |
| 11 | 364 |
| 12 | 952 |
| 13 | 1944 |
| 14 | 5169 |
| 15 | 10659 |
| 16 | 28842 |
| 17 | 60115 |
| 18 | 164450 |
| 19 | 345345 |
| 20 | 953814 |
| 21 | 2016144 |
| 22 | 5609760 |
| 23 | 11920740 |
| 24 | 33378072 |
| 25 | 71250060 |
| 26 | 200553733 |
| 27 | 429757960 |
| 28 | 1215177680 |
| 29 | 2612635888 |
| 30 | 7416503776 |