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 | 133 |
| 3 | 4140 |
| 4 | 154938 |
| 5 | 6398717 |
| 6 | 281086555 |
| 7 | 12882897819 |
| 8 | 609038885805 |
| 9 | 29481041746958 |
| 10 | 1453894927584477 |
| 11 | 72789271870852237 |
| 12 | 3689808842747726368 |
| 13 | 189006099916444293090 |
| 14 | 9768094831949586349262 |
| 15 | 508712466332195692590121 |
| 16 | 26670630123516854616641671 |
| 17 | 1406503552584980596900001922 |
| 18 | 74559627811441047591493767590 |