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) |
|---|---|
| 3 | 108 |
| 4 | 614 |
| 5 | 3840 |
| 6 | 26937 |
| 7 | 211722 |
| 8 | 1852300 |
| 9 | 17900118 |
| 10 | 189670655 |
| 11 | 2188938928 |
| 12 | 27349969842 |
| 13 | 368010246500 |
| 14 | 5307501200421 |
| 15 | 81699366763710 |
| 16 | 1337244268935960 |
| 17 | 23195236251394954 |
| 18 | 425069874742963563 |
| 19 | 8207267847726907028 |
| 20 | 166543057722717660670 |
| 21 | 3543666872978746093608 |
| 22 | 78898851731990085876113 |