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 | 1 |
| 4 | 63 |
| 5 | 665 |
| 6 | 3368 |
| 7 | 11592 |
| 8 | 31696 |
| 9 | 74361 |
| 10 | 156087 |
| 11 | 300993 |
| 12 | 542920 |
| 13 | 927648 |
| 14 | 1515416 |
| 15 | 2383745 |
| 16 | 3630375 |
| 17 | 5376505 |
| 18 | 7770336 |
| 19 | 10990728 |
| 20 | 15251160 |
| 21 | 20803993 |
| 22 | 27944847 |
| 23 | 37017281 |
| 24 | 48417776 |
| 25 | 62600832 |
| 26 | 80084368 |
| 27 | 101455425 |
| 28 | 127375983 |