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 | 3 |
| 2 | 14 |
| 3 | 60 |
| 4 | 248 |
| 5 | 336 |
| 6 | 4064 |
| 7 | 15120 |
| 8 | 16380 |
| 9 | 261888 |
| 10 | 1089270 |
| 11 | 11784960 |
| 12 | 16775168 |
| 13 | 22766400 |
| 14 | 71495424 |
| 15 | 229909120 |
| 16 | 689727360 |
| 17 | 738152448 |
| 18 | 4294934528 |
| 19 | 7091219520 |
| 20 | 15999197760 |
| 21 | 21930739200 |
| 22 | 25500590080 |
| 23 | 33216860160 |