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 | 27 |
| 3 | 351 |
| 4 | 5319 |
| 5 | 87885 |
| 6 | 1535517 |
| 7 | 27898101 |
| 8 | 521740197 |
| 9 | 9977087439 |
| 10 | 194191054263 |
| 11 | 3834392341779 |
| 12 | 76619557946475 |
| 13 | 1546479815079321 |
| 14 | 31482877148802873 |
| 15 | 645689728734541929 |
| 16 | 13328555370318744777 |
| 17 | 276704344407952939131 |
| 18 | 5773556701375333682355 |