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 | 1 |
| 2 | 2 |
| 3 | 16 |
| 4 | 122 |
| 5 | 925 |
| 6 | 7066 |
| 7 | 54560 |
| 8 | 426462 |
| 9 | 3372291 |
| 10 | 26956270 |
| 11 | 217614820 |
| 12 | 1772645420 |
| 13 | 14557912005 |
| 14 | 120446430162 |
| 15 | 1003264150080 |
| 16 | 8408233633984 |
| 17 | 70865259181716 |
| 18 | 600341163614280 |
| 19 | 5109974618238720 |
| 20 | 43685248156083450 |
| 21 | 374975710962745835 |
| 22 | 3230692210606121118 |