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 | 7 |
| 2 | 35 |
| 3 | 140 |
| 4 | 490 |
| 5 | 1547 |
| 6 | 4522 |
| 7 | 12404 |
| 8 | 32298 |
| 9 | 80430 |
| 10 | 192759 |
| 11 | 446656 |
| 12 | 1004598 |
| 13 | 2199953 |
| 14 | 4703104 |
| 15 | 9836820 |
| 16 | 20167210 |
| 17 | 40593651 |
| 18 | 80335164 |
| 19 | 156503088 |
| 20 | 300457906 |
| 21 | 568992893 |
| 22 | 1063818868 |
| 23 | 1965178600 |
| 24 | 3589328246 |
| 25 | 6485976525 |
| 26 | 11602141453 |
| 27 | 20555544212 |
| 28 | 36087448852 |