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 | 4 |
| 2 | 20 |
| 3 | 136 |
| 4 | 1360 |
| 5 | 21204 |
| 6 | 537748 |
| 7 | 22891448 |
| 8 | 1675538928 |
| 9 | 214841466180 |
| 10 | 48966357498452 |
| 11 | 20069542925092392 |
| 12 | 14932742187505262032 |
| 13 | 20328765555338724571508 |
| 14 | 50972424276515393704138196 |