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 | 9 |
| 2 | 85 |
| 3 | 837 |
| 4 | 8521 |
| 5 | 88929 |
| 6 | 944605 |
| 7 | 10155357 |
| 8 | 110061841 |
| 9 | 1199150649 |
| 10 | 13109949925 |
| 11 | 143644498677 |
| 12 | 1576134831961 |
| 13 | 17309800577169 |
| 14 | 190214028328045 |
| 15 | 2090997865462797 |
| 16 | 22991481397070881 |
| 17 | 252839829506640489 |
| 18 | 2780772863545070965 |
| 19 | 30585244671799959717 |
| 20 | 336414893599428810601 |