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 | 6 |
| 2 | 39 |
| 3 | 272 |
| 4 | 1995 |
| 5 | 15180 |
| 6 | 118755 |
| 7 | 949344 |
| 8 | 7721604 |
| 9 | 63698830 |
| 10 | 531697881 |
| 11 | 4482448656 |
| 12 | 38111876530 |
| 13 | 326439471960 |
| 14 | 2814095259675 |
| 15 | 24397023508416 |
| 16 | 212579132600076 |
| 17 | 1860620845932216 |
| 18 | 16351267454243260 |
| 19 | 144222309948974400 |
| 20 | 1276307560533365955 |
| 21 | 11329053395044653180 |