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 | 1 |
| 3 | 2 |
| 4 | 10 |
| 5 | 32 |
| 6 | 126 |
| 7 | 452 |
| 8 | 1716 |
| 9 | 6400 |
| 10 | 24310 |
| 11 | 92252 |
| 12 | 352716 |
| 13 | 1351616 |
| 14 | 5200300 |
| 15 | 20056584 |
| 16 | 77558760 |
| 17 | 300533760 |
| 18 | 1166803110 |
| 19 | 4537543340 |
| 20 | 17672631900 |
| 21 | 68923172032 |
| 22 | 269128937220 |
| 23 | 1052049129144 |
| 24 | 4116715363800 |