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 | 6 |
| 2 | 36 |
| 3 | 102 |
| 4 | 370 |
| 5 | 1232 |
| 6 | 4238 |
| 7 | 14406 |
| 8 | 49164 |
| 9 | 167530 |
| 10 | 571202 |
| 11 | 1947168 |
| 12 | 6638170 |
| 13 | 22629802 |
| 14 | 77146700 |
| 15 | 262997994 |
| 16 | 896578158 |
| 17 | 3056494736 |
| 18 | 10419796218 |
| 19 | 35521783770 |
| 20 | 121096145300 |
| 21 | 412824884294 |
| 22 | 1407347734502 |
| 23 | 4797742864320 |