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 | 0 |
| 2 | 5 |
| 3 | 26 |
| 4 | 257 |
| 5 | 3004 |
| 6 | 42277 |
| 7 | 694182 |
| 8 | 13027233 |
| 9 | 275027480 |
| 10 | 6451456421 |
| 11 | 166468606930 |
| 12 | 4685926374241 |
| 13 | 142896198878484 |
| 14 | 4692784128725253 |
| 15 | 165121528707826334 |
| 16 | 6197343209916830657 |
| 17 | 247136182723119609520 |
| 18 | 10434957969449887989445 |
| 19 | 465078400154112693602826 |