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 | 1 |
| 2 | 6 |
| 3 | 25 |
| 4 | 96 |
| 5 | 361 |
| 6 | 1350 |
| 7 | 5041 |
| 8 | 18816 |
| 9 | 70225 |
| 10 | 262086 |
| 11 | 978121 |
| 12 | 3650400 |
| 13 | 13623481 |
| 14 | 50843526 |
| 15 | 189750625 |
| 16 | 708158976 |
| 17 | 2642885281 |
| 18 | 9863382150 |
| 19 | 36810643321 |
| 20 | 137379191136 |
| 21 | 512706121225 |
| 22 | 1913445293766 |
| 23 | 7141075053841 |
| 24 | 26650854921600 |
| 25 | 99462344632561 |
| 26 | 371198523608646 |