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 | 4 |
| 3 | 16 |
| 4 | 60 |
| 5 | 216 |
| 6 | 756 |
| 7 | 2592 |
| 8 | 8748 |
| 9 | 29160 |
| 10 | 96228 |
| 11 | 314928 |
| 12 | 1023516 |
| 13 | 3306744 |
| 14 | 10628820 |
| 15 | 34012224 |
| 16 | 108413964 |
| 17 | 344373768 |
| 18 | 1090516932 |
| 19 | 3443737680 |
| 20 | 10847773692 |
| 21 | 34093003032 |
| 22 | 106928054964 |
| 23 | 334731302496 |
| 24 | 1046035320300 |
| 25 | 3263630199336 |
| 26 | 10167463313316 |
| 27 | 31632108085872 |