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 | 1 |
| 1 | 6 |
| 2 | 28 |
| 3 | 104 |
| 4 | 464 |
| 5 | 1696 |
| 6 | 7488 |
| 7 | 27264 |
| 8 | 120064 |
| 9 | 436736 |
| 10 | 1922048 |
| 11 | 6989824 |
| 12 | 30756864 |
| 13 | 111845376 |
| 14 | 492126208 |
| 15 | 1789558784 |
| 16 | 7874084864 |
| 17 | 28633071616 |
| 18 | 125985619968 |
| 19 | 458129670144 |
| 20 | 2015770968064 |
| 21 | 7330076819456 |
| 22 | 32252339683328 |
| 23 | 117281237499904 |
| 24 | 516037451710464 |