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 | 0 |
| 2 | 2 |
| 3 | 17 |
| 4 | 127 |
| 5 | 1003 |
| 6 | 8326 |
| 7 | 71038 |
| 8 | 618610 |
| 9 | 5481646 |
| 10 | 49221187 |
| 11 | 446590932 |
| 12 | 4087194991 |
| 13 | 37677478288 |
| 14 | 349465615584 |
| 15 | 3258501713644 |
| 16 | 30522628848972 |
| 17 | 287059041039078 |
| 18 | 2709339704446862 |
| 19 | 25652489700275636 |
| 20 | 243571629996128384 |
| 21 | 2318640708958531064 |
| 22 | 22123070798400775157 |