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 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 28 |
| 5 | 95 |
| 6 | 353 |
| 7 | 1435 |
| 8 | 6340 |
| 9 | 30205 |
| 10 | 154059 |
| 11 | 836181 |
| 12 | 4805816 |
| 13 | 29125915 |
| 14 | 185474289 |
| 15 | 1237159447 |
| 16 | 8620179448 |
| 17 | 62589847993 |
| 18 | 472554134275 |
| 19 | 3702702752513 |
| 20 | 30057098645316 |
| 21 | 252375781238167 |
| 22 | 2188733915100465 |
| 23 | 19579797280231795 |
| 24 | 180453411239741852 |
| 25 | 1711498126672376373 |