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 | 6 |
| 2 | 15 |
| 3 | 55 |
| 4 | 145 |
| 5 | 889 |
| 6 | 5089 |
| 7 | 55561 |
| 8 | 927889 |
| 9 | 6169249 |
| 10 | 39916921 |
| 11 | 678585889 |
| 12 | 13891047241 |
| 13 | 417210398089 |
| 14 | 1656387533161 |
| 15 | 56229997825849 |
| 16 | 481224167424529 |
| 17 | 11026310270976961 |
| 18 | 236887827111937369 |
| 19 | 10826413936386055921 |