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 | 3 |
| 2 | 9 |
| 3 | 26 |
| 4 | 76 |
| 5 | 221 |
| 6 | 644 |
| 7 | 1875 |
| 8 | 5461 |
| 9 | 15903 |
| 10 | 46314 |
| 11 | 134876 |
| 12 | 392791 |
| 13 | 1143896 |
| 14 | 3331289 |
| 15 | 9701475 |
| 16 | 28252921 |
| 17 | 82278978 |
| 18 | 239615244 |
| 19 | 697814501 |
| 20 | 2032195756 |
| 21 | 5918219771 |
| 22 | 17235212309 |
| 23 | 50192888175 |
| 24 | 146173193506 |
| 25 | 425689839228 |