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 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 0 |
| 8 | 0 |
| 9 | 20 |
| 10 | 224 |
| 11 | 1364 |
| 12 | 5984 |
| 13 | 21164 |
| 14 | 64064 |
| 15 | 172172 |
| 16 | 420992 |
| 17 | 952988 |
| 18 | 2022672 |
| 19 | 4065084 |
| 20 | 7794240 |
| 21 | 14346780 |
| 22 | 25473360 |
| 23 | 43815420 |
| 24 | 73244160 |
| 25 | 119362160 |
| 26 | 190057520 |
| 27 | 296373008 |