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 | 4 |
| 3 | 22 |
| 4 | 140 |
| 5 | 970 |
| 6 | 7196 |
| 7 | 56092 |
| 8 | 452064 |
| 9 | 3735700 |
| 10 | 31484244 |
| 11 | 269613896 |
| 12 | 2339571468 |
| 13 | 20529434520 |
| 14 | 181871459580 |
| 15 | 1624587752400 |
| 16 | 14617165101216 |