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 | 21 |
| 2 | 261 |
| 3 | 6126 |
| 4 | 120124 |
| 5 | 2547810 |
| 6 | 54485279 |
| 7 | 1157805351 |
| 8 | 24615811883 |
| 9 | 523548909308 |
| 10 | 11133382117666 |
| 11 | 236751472446562 |
| 12 | 5034642562404119 |
| 13 | 107064153494511600 |
| 14 | 2276766498890520783 |
| 15 | 48416455811053263714 |
| 16 | 1029597712238409457187 |