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) |
|---|---|
| 1 | 0 |
| 2 | 2 |
| 3 | 70 |
| 4 | 764 |
| 5 | 4718 |
| 6 | 20658 |
| 7 | 71616 |
| 8 | 209752 |
| 9 | 540416 |
| 10 | 1259050 |
| 11 | 2704494 |
| 12 | 5433420 |
| 13 | 10320054 |
| 14 | 18688026 |
| 15 | 32478032 |
| 16 | 54460064 |
| 17 | 88495536 |
| 18 | 139857842 |
| 19 | 215617062 |
| 20 | 325102172 |
| 21 | 480442174 |
| 22 | 697204602 |
| 23 | 995133456 |
| 24 | 1399002496 |
| 25 | 1939589056 |