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 | 1 |
| 2 | 6 |
| 3 | 16 |
| 4 | 80 |
| 5 | 296 |
| 6 | 1296 |
| 7 | 5216 |
| 8 | 21952 |
| 9 | 90304 |
| 10 | 375936 |
| 11 | 1555456 |
| 12 | 6456320 |
| 13 | 26754560 |
| 14 | 110963712 |
| 15 | 460015616 |
| 16 | 1907494912 |
| 17 | 7908659200 |
| 18 | 32792076288 |
| 19 | 135963148288 |
| 20 | 563742310400 |
| 21 | 2337417887744 |
| 22 | 9691567030272 |
| 23 | 40183767891968 |
| 24 | 166612591968256 |
| 25 | 690819710058496 |