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 | 9 |
| 3 | 71 |
| 4 | 963 |
| 5 | 9873 |
| 6 | 231749 |
| 7 | 2976863 |
| 8 | 86348423 |
| 9 | 1824883450 |
| 10 | 55584932826 |
| 11 | 1104642697680 |
| 12 | 64932555347084 |
| 13 | 1366828157222090 |
| 14 | 61273696016238014 |
| 15 | 2581786206601959958 |
| 16 | 129797968403021602450 |
| 17 | 3678372903755436314440 |
| 18 | 295835829367866540495396 |