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) |
|---|---|
| 0 | 1 |
| 1 | 4 |
| 2 | 17 |
| 3 | 54 |
| 4 | 145 |
| 5 | 368 |
| 6 | 945 |
| 7 | 2530 |
| 8 | 7073 |
| 9 | 20412 |
| 10 | 60049 |
| 11 | 178478 |
| 12 | 533169 |
| 13 | 1596520 |
| 14 | 4785713 |
| 15 | 14352282 |
| 16 | 43050817 |
| 17 | 129145076 |
| 18 | 387426321 |
| 19 | 1162268326 |
| 20 | 3486792401 |
| 21 | 10460362464 |
| 22 | 31381070257 |
| 23 | 94143190994 |
| 24 | 282429550305 |
| 25 | 847288625068 |