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 | 2 |
| 2 | 32 |
| 3 | 338 |
| 4 | 3200 |
| 5 | 29282 |
| 6 | 264992 |
| 7 | 2389298 |
| 8 | 21516800 |
| 9 | 193690562 |
| 10 | 1743333152 |
| 11 | 15690352658 |
| 12 | 141214236800 |
| 13 | 1270931319842 |
| 14 | 11438391444512 |
| 15 | 102945551698418 |
| 16 | 926510051379200 |
| 17 | 8338590720693122 |
| 18 | 75047317261079072 |
| 19 | 675425857674234578 |
| 20 | 6078832726041680000 |
| 21 | 54709494555295826402 |