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 | -3 |
| 3 | -11 |
| 4 | -49 |
| 5 | -244 |
| 6 | -1301 |
| 7 | -7265 |
| 8 | -41945 |
| 9 | -248357 |
| 10 | -1499838 |
| 11 | -9202478 |
| 12 | -57204263 |
| 13 | -359491066 |
| 14 | -2280171089 |
| 15 | -14578108497 |
| 16 | -93850280001 |
| 17 | -607856133804 |
| 18 | -3958143058643 |
| 19 | -25897182540675 |
| 20 | -170164359751174 |
| 21 | -1122422557526850 |
| 22 | -7429480035700452 |