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) |
|---|---|
| 3 | 1 |
| 4 | 10 |
| 5 | 75 |
| 6 | 372 |
| 7 | 1796 |
| 8 | 7796 |
| 9 | 33352 |
| 10 | 138790 |
| 11 | 571995 |
| 12 | 2334558 |
| 13 | 9473195 |
| 14 | 38258984 |
| 15 | 153981400 |
| 16 | 618042736 |
| 17 | 2475405456 |
| 18 | 9897862062 |
| 19 | 39523226642 |
| 20 | 157650156506 |
| 21 | 628287555844 |
| 22 | 2502170730172 |
| 23 | 9959281642416 |
| 24 | 39622214018100 |
| 25 | 157575049910690 |
| 26 | 626477638980782 |
| 27 | 2490112612092175 |