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 | 2 |
| 2 | 10 |
| 3 | 76 |
| 4 | 764 |
| 5 | 9496 |
| 6 | 140152 |
| 7 | 2390480 |
| 8 | 46206736 |
| 9 | 997313824 |
| 10 | 23758664096 |
| 11 | 618884638912 |
| 12 | 17492190577600 |
| 13 | 532985208200576 |
| 14 | 17411277367391104 |
| 15 | 606917269909048576 |
| 16 | 22481059424730751232 |
| 17 | 881687990282453393920 |
| 18 | 36494410645223834692096 |
| 19 | 1589659519990672490875904 |