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 | 15 |
| 2 | 225 |
| 3 | 240 |
| 4 | 504 |
| 5 | 900 |
| 6 | 1776 |
| 7 | 3456 |
| 8 | 6300 |
| 9 | 12656 |
| 10 | 24124 |
| 11 | 45276 |
| 12 | 88400 |
| 13 | 170280 |
| 14 | 323760 |
| 15 | 618496 |
| 16 | 1202400 |
| 17 | 2300200 |
| 18 | 4360824 |
| 19 | 8464860 |
| 20 | 16284576 |
| 21 | 30897024 |
| 22 | 59537156 |
| 23 | 115023968 |
| 24 | 219164204 |
| 25 | 419459908 |
| 26 | 811024296 |
| 27 | 1553149080 |
| 28 | 2962595040 |