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 | 0 |
| 2 | 9396 |
| 3 | 284528 |
| 4 | 3309660 |
| 5 | 21996036 |
| 6 | 103632480 |
| 7 | 384538752 |
| 8 | 1195104618 |
| 9 | 3253783500 |
| 10 | 7971340896 |
| 11 | 17905302720 |
| 12 | 37530681590 |
| 13 | 74139276672 |
| 14 | 139067432280 |
| 15 | 250102136592 |
| 16 | 433070833500 |
| 17 | 724358442744 |
| 18 | 1178016364548 |
| 19 | 1866143480400 |
| 20 | 2883345017508 |
| 21 | 4367172766500 |