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 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 6 |
| 5 | 12 |
| 6 | 24 |
| 7 | 66 |
| 8 | 132 |
| 9 | 264 |
| 10 | 792 |
| 11 | 3960 |
| 12 | 14652 |
| 13 | 26664 |
| 14 | 29304 |
| 15 | 79992 |
| 16 | 146520 |
| 17 | 399960 |
| 18 | 1025640 |
| 19 | 2666664 |
| 20 | 7999992 |
| 21 | 13333320 |
| 22 | 39999960 |
| 23 | 269333064 |
| 24 | 807999192 |
| 25 | 1346665320 |
| 26 | 4039995960 |
| 27 | 28279971720 |
| 28 | 7999999999992 |
| 29 | 8080799919192 |
| 30 | 13333333333320 |
| 31 | 13467999865320 |
| 32 | 39999999999960 |
| 33 | 40403999595960 |