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 | 0 |
| 2 | 3 |
| 3 | 8 |
| 4 | 13 |
| 5 | 52 |
| 6 | 119 |
| 7 | 308 |
| 8 | 873 |
| 9 | 2184 |
| 10 | 5867 |
| 11 | 15552 |
| 12 | 40581 |
| 13 | 107836 |
| 14 | 283871 |
| 15 | 748076 |
| 16 | 1976545 |
| 17 | 5208784 |
| 18 | 13743315 |
| 19 | 36260088 |
| 20 | 95627773 |
| 21 | 252289476 |
| 22 | 665499975 |
| 23 | 1755466916 |
| 24 | 4630903129 |
| 25 | 12215645848 |
| 26 | 32223689915 |
| 27 | 85003275440 |
| 28 | 224228961909 |
| 29 | 591494654412 |
| 30 | 1560303157679 |