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 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 16 |
| 5 | 52 |
| 6 | 172 |
| 7 | 586 |
| 8 | 2048 |
| 9 | 7286 |
| 10 | 26216 |
| 11 | 95326 |
| 12 | 349536 |
| 13 | 1290556 |
| 14 | 4793492 |
| 15 | 17895736 |
| 16 | 67108864 |
| 17 | 252645136 |
| 18 | 954437292 |
| 19 | 3616814566 |
| 20 | 13743895360 |
| 21 | 52357696956 |
| 22 | 199911205052 |
| 23 | 764877654106 |
| 24 | 2932031008768 |
| 25 | 11258999068468 |
| 26 | 43303842570872 |
| 27 | 166799986203766 |
| 28 | 643371375338656 |
| 29 | 2484744621997516 |