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 | 2 |
| 1 | 4 |
| 2 | 14 |
| 3 | 64 |
| 4 | 314 |
| 5 | 1564 |
| 6 | 7814 |
| 7 | 39064 |
| 8 | 195314 |
| 9 | 976564 |
| 10 | 4882814 |
| 11 | 24414064 |
| 12 | 122070314 |
| 13 | 610351564 |
| 14 | 3051757814 |
| 15 | 15258789064 |
| 16 | 76293945314 |
| 17 | 381469726564 |
| 18 | 1907348632814 |
| 19 | 9536743164064 |
| 20 | 47683715820314 |