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 | 3 |
| 2 | 8 |
| 3 | 28 |
| 4 | 104 |
| 5 | 400 |
| 6 | 1568 |
| 7 | 6208 |
| 8 | 24704 |
| 9 | 98560 |
| 10 | 393728 |
| 11 | 1573888 |
| 12 | 6293504 |
| 13 | 25169920 |
| 14 | 100671488 |
| 15 | 402669568 |
| 16 | 1610645504 |
| 17 | 6442516480 |
| 18 | 25769934848 |
| 19 | 103079477248 |
| 20 | 412317384704 |
| 21 | 1649268490240 |
| 22 | 6597071863808 |
| 23 | 26388283260928 |