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 | 2 |
| 1 | 3 |
| 2 | 7 |
| 3 | 16 |
| 4 | 41 |
| 5 | 146 |
| 6 | 757 |
| 7 | 5090 |
| 8 | 40385 |
| 9 | 362962 |
| 10 | 3628901 |
| 11 | 39916922 |
| 12 | 479001745 |
| 13 | 6227020970 |
| 14 | 87178291397 |
| 15 | 1307674368226 |
| 16 | 20922789888257 |
| 17 | 355687428096290 |
| 18 | 6402373705728325 |
| 19 | 121645100408832362 |
| 20 | 2432902008176640401 |
| 21 | 51090942171709440442 |
| 22 | 1124000727777607680485 |