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 | 0 |
| 1 | 2 |
| 2 | 4 |
| 3 | 11 |
| 4 | 25 |
| 5 | 62 |
| 6 | 162 |
| 7 | 433 |
| 8 | 1175 |
| 9 | 3229 |
| 10 | 9042 |
| 11 | 25549 |
| 12 | 73050 |
| 13 | 210356 |
| 14 | 610041 |
| 15 | 1779830 |
| 16 | 5218745 |
| 17 | 15372304 |
| 18 | 45455747 |
| 19 | 134882577 |
| 20 | 401480918 |
| 21 | 1198344171 |
| 22 | 3585783711 |
| 23 | 10754085805 |
| 24 | 32319203663 |
| 25 | 97312548674 |
| 26 | 293515297707 |
| 27 | 886720888966 |
| 28 | 2682778745396 |
| 29 | 8127887397064 |