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 | 0 |
| 1 | 0 |
| 2 | 54 |
| 3 | 696 |
| 4 | 4020 |
| 5 | 15480 |
| 6 | 46410 |
| 7 | 117264 |
| 8 | 261576 |
| 9 | 530640 |
| 10 | 998910 |
| 11 | 1770120 |
| 12 | 2984124 |
| 13 | 4824456 |
| 14 | 7526610 |
| 15 | 11387040 |
| 16 | 16772880 |
| 17 | 24132384 |
| 18 | 34006086 |
| 19 | 47038680 |
| 20 | 63991620 |
| 21 | 85756440 |
| 22 | 113368794 |
| 23 | 148023216 |
| 24 | 191088600 |
| 25 | 244124400 |
| 26 | 308897550 |
| 27 | 387400104 |
| 28 | 481867596 |
| 29 | 594798120 |