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 | 2 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 14 |
| 6 | 50 |
| 7 | 194 |
| 8 | 750 |
| 9 | 2934 |
| 10 | 11557 |
| 11 | 46010 |
| 12 | 184784 |
| 13 | 748678 |
| 14 | 3056308 |
| 15 | 12562908 |
| 16 | 51952261 |
| 17 | 216011544 |
| 18 | 902512979 |
| 19 | 3787287378 |
| 20 | 15955748048 |
| 21 | 67462625834 |
| 22 | 286172617162 |
| 23 | 1217561851258 |
| 24 | 5194521586232 |