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 | 1 |
| 2 | 2 |
| 3 | 8 |
| 4 | 36 |
| 5 | 176 |
| 6 | 864 |
| 7 | 4304 |
| 8 | 21448 |
| 9 | 107168 |
| 10 | 535488 |
| 11 | 2677088 |
| 12 | 13383712 |
| 13 | 66916832 |
| 14 | 334575552 |
| 15 | 1672869152 |
| 16 | 8364302864 |
| 17 | 41821471424 |
| 18 | 209107142784 |
| 19 | 1045535499584 |
| 20 | 5227676426944 |
| 21 | 26138381063744 |
| 22 | 130691899964544 |
| 23 | 653459494468544 |
| 24 | 3267297445575296 |
| 25 | 16336487201109056 |