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 | 50 |
| 2 | 390 |
| 3 | 1680 |
| 4 | 5320 |
| 5 | 13860 |
| 6 | 31500 |
| 7 | 64680 |
| 8 | 122760 |
| 9 | 218790 |
| 10 | 370370 |
| 11 | 600600 |
| 12 | 939120 |
| 13 | 1423240 |
| 14 | 2099160 |
| 15 | 3023280 |
| 16 | 4263600 |
| 17 | 5901210 |
| 18 | 8031870 |
| 19 | 10767680 |
| 20 | 14238840 |
| 21 | 18595500 |
| 22 | 24009700 |
| 23 | 30677400 |
| 24 | 38820600 |
| 25 | 48689550 |
| 26 | 60565050 |
| 27 | 74760840 |
| 28 | 91626080 |
| 29 | 111547920 |
| 30 | 134954160 |