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 | 220 |
| 2 | 4220 |
| 3 | 25220 |
| 4 | 84280 |
| 5 | 217800 |
| 6 | 456640 |
| 7 | 873090 |
| 8 | 1501520 |
| 9 | 2436020 |
| 10 | 3736540 |
| 11 | 5523970 |
| 12 | 7830800 |
| 13 | 10879460 |
| 14 | 14665340 |
| 15 | 19398660 |
| 16 | 25173960 |
| 17 | 32203320 |
| 18 | 40502280 |
| 19 | 50458120 |
| 20 | 61995140 |
| 21 | 75517160 |