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 | 9 |
| 2 | 44 |
| 3 | 170 |
| 4 | 576 |
| 5 | 1792 |
| 6 | 5248 |
| 7 | 14688 |
| 8 | 39680 |
| 9 | 104192 |
| 10 | 267264 |
| 11 | 672256 |
| 12 | 1662976 |
| 13 | 4055040 |
| 14 | 9764864 |
| 15 | 23257088 |
| 16 | 54853632 |
| 17 | 128253952 |
| 18 | 297533440 |
| 19 | 685375488 |
| 20 | 1568669696 |
| 21 | 3569352704 |
| 22 | 8078229504 |
| 23 | 18192793600 |
| 24 | 40785412096 |
| 25 | 91049951232 |