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 | 2 |
| 4 | 4 |
| 5 | 8 |
| 6 | 18 |
| 7 | 40 |
| 8 | 95 |
| 9 | 227 |
| 10 | 557 |
| 11 | 1382 |
| 12 | 3485 |
| 13 | 8865 |
| 14 | 22790 |
| 15 | 59022 |
| 16 | 153972 |
| 17 | 404066 |
| 18 | 1066236 |
| 19 | 2826885 |
| 20 | 7527411 |
| 21 | 20121154 |