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 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 8 |
| 6 | 35 |
| 7 | 144 |
| 8 | 425 |
| 9 | 1035 |
| 10 | 2436 |
| 11 | 6140 |
| 12 | 16922 |
| 13 | 49176 |
| 14 | 144117 |
| 15 | 410571 |
| 16 | 1135249 |
| 17 | 3089181 |
| 18 | 8424096 |
| 19 | 23191590 |
| 20 | 64417192 |
| 21 | 179639575 |
| 22 | 500440977 |
| 23 | 1389439997 |
| 24 | 3846685210 |
| 25 | 10639680698 |
| 26 | 29446636078 |
| 27 | 81589820105 |
| 28 | 226250592841 |