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 | 15 |
| 2 | 250 |
| 3 | 4250 |
| 4 | 72500 |
| 5 | 1237500 |
| 6 | 21125000 |
| 7 | 360625000 |
| 8 | 6156250000 |
| 9 | 105093750000 |
| 10 | 1794062500000 |
| 11 | 30626562500000 |
| 12 | 522828125000000 |
| 13 | 8925234375000000 |
| 14 | 152363281250000000 |
| 15 | 2601003906250000000 |
| 16 | 44401914062500000000 |