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) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 10 |
| 4 | 43 |
| 5 | 231 |
| 6 | 1531 |
| 7 | 11068 |
| 8 | 89895 |
| 9 | 820543 |
| 10 | 8484871 |
| 11 | 95647476 |
| 12 | 1186289083 |
| 13 | 15648402355 |
| 14 | 221728356123 |
| 15 | 3354790995676 |
| 16 | 53999879550991 |
| 17 | 936289020367263 |
| 18 | 17163114699673615 |
| 19 | 328827078340587148 |
| 20 | 6630244432204704771 |
| 21 | 139769193881466850051 |
| 22 | 3092293682224076627683 |