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 | 1 |
| 2 | 13 |
| 3 | 53 |
| 4 | 1241 |
| 5 | 5161 |
| 6 | 121573 |
| 7 | 505693 |
| 8 | 11912881 |
| 9 | 49552721 |
| 10 | 1167340733 |
| 11 | 4855660933 |
| 12 | 114387478921 |
| 13 | 475805218681 |
| 14 | 11208805593493 |
| 15 | 46624055769773 |
| 16 | 1098348560683361 |
| 17 | 4568681660219041 |
| 18 | 107626950141375853 |
| 19 | 447684178645696213 |
| 20 | 10546342765294150201 |