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 | 2 |
| 2 | 20 |
| 3 | 102 |
| 4 | 360 |
| 5 | 1002 |
| 6 | 2364 |
| 7 | 4942 |
| 8 | 9424 |
| 9 | 16722 |
| 10 | 28004 |
| 11 | 44726 |
| 12 | 68664 |
| 13 | 101946 |
| 14 | 147084 |
| 15 | 207006 |
| 16 | 285088 |
| 17 | 385186 |
| 18 | 511668 |
| 19 | 669446 |
| 20 | 864008 |
| 21 | 1101450 |
| 22 | 1388508 |
| 23 | 1732590 |
| 24 | 2141808 |
| 25 | 2625010 |
| 26 | 3191812 |
| 27 | 3852630 |
| 28 | 4618712 |
| 29 | 5502170 |
| 30 | 6516012 |