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 | 6 |
| 2 | 36 |
| 3 | 102 |
| 4 | 289 |
| 5 | 1071 |
| 6 | 3969 |
| 7 | 13230 |
| 8 | 44100 |
| 9 | 153090 |
| 10 | 531441 |
| 11 | 1815939 |
| 12 | 6205081 |
| 13 | 21332924 |
| 14 | 73342096 |
| 15 | 251550372 |
| 16 | 862773129 |
| 17 | 2961885201 |
| 18 | 10168100569 |
| 19 | 34894442176 |
| 20 | 119749218304 |
| 21 | 411007092416 |
| 22 | 1410671672089 |
| 23 | 4841491994817 |