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 | 3 |
| 5 | 8 |
| 6 | 15 |
| 7 | 144 |
| 8 | 35 |
| 9 | 5760 |
| 10 | 315 |
| 11 | 5600 |
| 12 | 693 |
| 13 | 43545600 |
| 14 | 1001 |
| 15 | 6706022400 |
| 16 | 6435 |
| 17 | 14014 |
| 18 | 109395 |
| 19 | 376610217984000 |
| 20 | 46189 |
| 21 | 128047474114560000 |
| 22 | 323323 |
| 23 | 2540395 |
| 24 | 2028117 |
| 25 | 26976017466662584320000 |
| 26 | 96577 |
| 27 | 3241475864250624 |
| 28 | 35102025 |
| 29 | 2126818694000 |
| 30 | 5386025 |