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 | 5 |
| 2 | 7 |
| 3 | 13 |
| 4 | 31 |
| 5 | 83 |
| 6 | 283 |
| 7 | 883 |
| 8 | 3643 |
| 9 | 12323 |
| 10 | 58243 |
| 11 | 1106563 |
| 12 | 4188803 |
| 13 | 2504902403 |
| 14 | 17041024003 |
| 15 | 72642169603 |
| 16 | 2324549427203 |
| 17 | 126757680265216003 |
| 18 | 38900816605808456499200003 |
| 19 | 26070192823309041523916800003 |
| 20 | 254451773522587035734629406212096000003 |