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 | 12 |
| 3 | 30 |
| 4 | 60 |
| 5 | 180 |
| 6 | 210 |
| 7 | 420 |
| 8 | 1260 |
| 9 | 2310 |
| 10 | 4620 |
| 11 | 13860 |
| 12 | 30030 |
| 13 | 60060 |
| 14 | 180180 |
| 15 | 510510 |
| 16 | 1021020 |
| 17 | 3063060 |
| 18 | 9699690 |
| 19 | 19399380 |
| 20 | 58198140 |
| 21 | 223092870 |
| 22 | 446185740 |
| 23 | 1338557220 |
| 24 | 6469693230 |
| 25 | 12939386460 |
| 26 | 38818159380 |
| 27 | 194090796900 |
| 28 | 200560490130 |
| 29 | 401120980260 |
| 30 | 1203362940780 |
| 31 | 6016814703900 |