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 | 7 |
| 3 | 40 |
| 4 | 324 |
| 5 | 3336 |
| 6 | 41192 |
| 7 | 590480 |
| 8 | 9623944 |
| 9 | 175703056 |
| 10 | 3552295752 |
| 11 | 78802665120 |
| 12 | 1903505233064 |
| 13 | 49743146641616 |
| 14 | 1398474578414632 |
| 15 | 42092742475096960 |
| 16 | 1350629892258170184 |
| 17 | 46025643554111478576 |