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) |
|---|---|
| 2 | 1 |
| 3 | 10 |
| 4 | 73 |
| 5 | 520 |
| 6 | 3967 |
| 7 | 33334 |
| 8 | 309661 |
| 9 | 3166468 |
| 10 | 35416555 |
| 11 | 430546642 |
| 12 | 5655609529 |
| 13 | 79856902816 |
| 14 | 1206424711303 |
| 15 | 19419937594990 |
| 16 | 331860183278677 |
| 17 | 6000534640290364 |
| 18 | 114462875817046051 |
| 19 | 2297294297649673738 |
| 20 | 48394006967070653425 |