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 | 60 |
| 2 | 1155 |
| 3 | 12320 |
| 4 | 90090 |
| 5 | 504504 |
| 6 | 2312310 |
| 7 | 9060480 |
| 8 | 31286970 |
| 9 | 97337240 |
| 10 | 277411134 |
| 11 | 733649280 |
| 12 | 1818838840 |
| 13 | 4261894560 |
| 14 | 9502285320 |
| 15 | 20271542016 |
| 16 | 41572498275 |
| 17 | 82281899700 |
| 18 | 157706974425 |
| 19 | 293570877600 |
| 20 | 532097215650 |
| 21 | 941124327000 |
| 22 | 1627522854750 |
| 23 | 2756636064000 |