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 | 5 |
| 2 | 25 |
| 3 | 120 |
| 4 | 565 |
| 5 | 2615 |
| 6 | 11950 |
| 7 | 54045 |
| 8 | 242365 |
| 9 | 1079240 |
| 10 | 4777225 |
| 11 | 21038595 |
| 12 | 92244790 |
| 13 | 402898865 |
| 14 | 1753806625 |
| 15 | 7611458520 |
| 16 | 32945585965 |
| 17 | 142262759615 |
| 18 | 612991045150 |
| 19 | 2636186279445 |
| 20 | 11317111447765 |
| 21 | 48506655275240 |
| 22 | 207603081203425 |