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 | 5 |
| 1 | 46 |
| 2 | 452 |
| 3 | 4504 |
| 4 | 45008 |
| 5 | 450016 |
| 6 | 4500032 |
| 7 | 45000064 |
| 8 | 450000128 |
| 9 | 4500000256 |
| 10 | 45000000512 |
| 11 | 450000001024 |
| 12 | 4500000002048 |
| 13 | 45000000004096 |
| 14 | 450000000008192 |
| 15 | 4500000000016384 |
| 16 | 45000000000032768 |
| 17 | 450000000000065536 |
| 18 | 4500000000000131072 |
| 19 | 45000000000000262144 |