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 | 0 |
| 2 | 3 |
| 3 | 22 |
| 4 | 207 |
| 5 | 2412 |
| 6 | 31754 |
| 7 | 452640 |
| 8 | 6840774 |
| 9 | 108088232 |
| 10 | 1768560270 |
| 11 | 29764630632 |
| 12 | 512705615350 |
| 13 | 9005206632672 |
| 14 | 160810554015408 |
| 15 | 2912940755956084 |
| 16 | 53424552150523386 |