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 | 4 |
| 2 | 30 |
| 3 | 114 |
| 4 | 310 |
| 5 | 690 |
| 6 | 1344 |
| 7 | 2380 |
| 8 | 3924 |
| 9 | 6120 |
| 10 | 9130 |
| 11 | 13134 |
| 12 | 18330 |
| 13 | 24934 |
| 14 | 33180 |
| 15 | 43320 |
| 16 | 55624 |
| 17 | 70380 |
| 18 | 87894 |
| 19 | 108490 |
| 20 | 132510 |
| 21 | 160314 |
| 22 | 192280 |
| 23 | 228804 |
| 24 | 270300 |
| 25 | 317200 |
| 26 | 369954 |
| 27 | 429030 |
| 28 | 494914 |
| 29 | 568110 |
| 30 | 649140 |