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 | 7 |
| 2 | 61 |
| 3 | 547 |
| 4 | 4921 |
| 5 | 44287 |
| 6 | 398581 |
| 7 | 3587227 |
| 8 | 32285041 |
| 9 | 290565367 |
| 10 | 2615088301 |
| 11 | 23535794707 |
| 12 | 211822152361 |
| 13 | 1906399371247 |
| 14 | 17157594341221 |
| 15 | 154418349070987 |
| 16 | 1389765141638881 |
| 17 | 12507886274749927 |
| 18 | 112570976472749341 |