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 | 4 |
| 4 | 11 |
| 5 | 35 |
| 6 | 114 |
| 7 | 392 |
| 8 | 1381 |
| 9 | 4998 |
| 10 | 18292 |
| 11 | 67791 |
| 12 | 253182 |
| 13 | 952527 |
| 14 | 3603389 |
| 15 | 13699516 |
| 16 | 52300071 |
| 17 | 200406183 |
| 18 | 770424072 |
| 19 | 2970400815 |
| 20 | 11482442855 |
| 21 | 44491876993 |
| 22 | 172766491178 |
| 23 | 672186631950 |
| 24 | 2619995178793 |
| 25 | 10228902801505 |
| 26 | 39996341268584 |
| 27 | 156612023001490 |
| 28 | 614044347934591 |