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 | 0 |
| 1 | 0 |
| 2 | 1 |
| 3 | 5 |
| 4 | 22 |
| 5 | 96 |
| 6 | 422 |
| 7 | 1871 |
| 8 | 8360 |
| 9 | 37610 |
| 10 | 170222 |
| 11 | 774561 |
| 12 | 3541487 |
| 13 | 16263250 |
| 14 | 74981226 |
| 15 | 346957923 |
| 16 | 1610847944 |
| 17 | 7501970397 |
| 18 | 35038158569 |
| 19 | 164083453482 |
| 20 | 770312822822 |
| 21 | 3624741537711 |
| 22 | 17093452878067 |
| 23 | 80773023036909 |