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 | 420 |
| 2 | 21870 |
| 3 | 331240 |
| 4 | 2128260 |
| 5 | 8972712 |
| 6 | 29822520 |
| 7 | 80027280 |
| 8 | 193511790 |
| 9 | 409172940 |
| 10 | 825736296 |
| 11 | 1509537960 |
| 12 | 2698852520 |
| 13 | 4472616120 |
| 14 | 7347537600 |
| 15 | 11335886864 |
| 16 | 17520853380 |
| 17 | 25553816400 |
| 18 | 37658603350 |
| 19 | 52706867640 |
| 20 | 74655559272 |
| 21 | 100969845200 |
| 22 | 138840872040 |
| 23 | 182317633680 |