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) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 8 |
| 3 | 27 |
| 4 | 124 |
| 5 | 725 |
| 6 | 5046 |
| 7 | 40327 |
| 8 | 362888 |
| 9 | 3628809 |
| 10 | 39916810 |
| 11 | 479001611 |
| 12 | 6227020812 |
| 13 | 87178291213 |
| 14 | 1307674368014 |
| 15 | 20922789888015 |
| 16 | 355687428096016 |
| 17 | 6402373705728017 |
| 18 | 121645100408832018 |
| 19 | 2432902008176640019 |
| 20 | 51090942171709440020 |
| 21 | 1124000727777607680021 |
| 22 | 25852016738884976640022 |