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 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 11 |
| 5 | 26 |
| 6 | 66 |
| 7 | 161 |
| 8 | 420 |
| 9 | 1093 |
| 10 | 2916 |
| 11 | 7819 |
| 12 | 21304 |
| 13 | 58321 |
| 14 | 161233 |
| 15 | 448090 |
| 16 | 1253252 |
| 17 | 3521389 |
| 18 | 9941693 |
| 19 | 28175716 |
| 20 | 80152141 |
| 21 | 228747967 |
| 22 | 654817275 |
| 23 | 1879602446 |
| 24 | 5408974390 |
| 25 | 15601662378 |
| 26 | 45098766532 |
| 27 | 130624550412 |