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 | 0 |
| 1 | 1 |
| 2 | 40 |
| 3 | 270 |
| 4 | 1344 |
| 5 | 3250 |
| 6 | 10800 |
| 7 | 17150 |
| 8 | 43520 |
| 9 | 66339 |
| 10 | 130000 |
| 11 | 162382 |
| 12 | 362880 |
| 13 | 373490 |
| 14 | 686000 |
| 15 | 877500 |
| 16 | 1396736 |
| 17 | 1424770 |
| 18 | 2653560 |
| 19 | 2482958 |
| 20 | 4368000 |
| 21 | 4630500 |
| 22 | 6495280 |
| 23 | 6448510 |
| 24 | 11750400 |
| 25 | 10171875 |
| 26 | 14939600 |
| 27 | 16140060 |
| 28 | 23049600 |
| 29 | 20535538 |
| 30 | 35100000 |
| 31 | 28658942 |
| 32 | 44728320 |