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 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 2 |
| 7 | 8 |
| 8 | 26 |
| 9 | 74 |
| 10 | 194 |
| 11 | 482 |
| 12 | 1152 |
| 13 | 2674 |
| 14 | 6068 |
| 15 | 13524 |
| 16 | 29704 |
| 17 | 64460 |
| 18 | 138482 |
| 19 | 294988 |
| 20 | 623834 |
| 21 | 1311086 |
| 22 | 2740666 |
| 23 | 5702270 |
| 24 | 11815752 |
| 25 | 24395678 |
| 26 | 50209572 |
| 27 | 103048168 |
| 28 | 210965064 |
| 29 | 430938832 |
| 30 | 878534170 |