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 | 4 |
| 1 | 56 |
| 2 | 496 |
| 3 | 4064 |
| 4 | 32704 |
| 5 | 262016 |
| 6 | 2096896 |
| 7 | 16776704 |
| 8 | 134216704 |
| 9 | 1073739776 |
| 10 | 8589930496 |
| 11 | 68719468544 |
| 12 | 549755797504 |
| 13 | 4398046478336 |
| 14 | 35184372023296 |
| 15 | 281474976579584 |
| 16 | 2251799813423104 |
| 17 | 18014398508957696 |
| 18 | 144115188074807296 |