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 | 0 |
| 3 | 2080 |
| 4 | 27768 |
| 5 | 181032 |
| 6 | 807040 |
| 7 | 2817240 |
| 8 | 8271480 |
| 9 | 21328048 |
| 10 | 49692672 |
| 11 | 106717680 |
| 12 | 214322680 |
| 13 | 406928280 |
| 14 | 736614528 |
| 15 | 1279735912 |
| 16 | 2145244920 |
| 17 | 3484996320 |
| 18 | 5506324480 |
| 19 | 8487206208 |
| 20 | 12794341752 |
| 21 | 18904506760 |
| 22 | 27429548160 |
| 23 | 39145417080 |
| 24 | 55025652088 |
| 25 | 76279746192 |