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 | 2 |
| 3 | 6 |
| 4 | 24 |
| 5 | 120 |
| 6 | 540 |
| 7 | 1996 |
| 8 | 6196 |
| 9 | 16732 |
| 10 | 40459 |
| 11 | 89519 |
| 12 | 184185 |
| 13 | 356721 |
| 14 | 656475 |
| 15 | 1156443 |
| 16 | 1961563 |
| 17 | 3219019 |
| 18 | 5130856 |
| 19 | 7969228 |
| 20 | 12094622 |
| 21 | 17977422 |
| 22 | 26223198 |
| 23 | 37602126 |
| 24 | 53082966 |
| 25 | 73872046 |
| 26 | 101457721 |
| 27 | 137660797 |
| 28 | 184691431 |
| 29 | 245213039 |
| 30 | 322413765 |
| 31 | 420086085 |
| 32 | 542715141 |