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 | 8 |
| 2 | 510 |
| 3 | 9840 |
| 4 | 87380 |
| 5 | 488280 |
| 6 | 2015538 |
| 7 | 6725600 |
| 8 | 19173960 |
| 9 | 48427560 |
| 10 | 111111110 |
| 11 | 235794768 |
| 12 | 469070940 |
| 13 | 883708280 |
| 14 | 1589311290 |
| 15 | 2745954240 |
| 16 | 4581298448 |
| 17 | 7411742280 |
| 18 | 11668193550 |
| 19 | 17927094320 |
| 20 | 26947368420 |
| 21 | 39714002328 |
| 22 | 57489010370 |
| 23 | 81870575520 |
| 24 | 114861197400 |