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 | 2 |
| 1 | 13 |
| 2 | 89 |
| 3 | 610 |
| 4 | 4181 |
| 5 | 28657 |
| 6 | 196418 |
| 7 | 1346269 |
| 8 | 9227465 |
| 9 | 63245986 |
| 10 | 433494437 |
| 11 | 2971215073 |
| 12 | 20365011074 |
| 13 | 139583862445 |
| 14 | 956722026041 |
| 15 | 6557470319842 |
| 16 | 44945570212853 |
| 17 | 308061521170129 |
| 18 | 2111485077978050 |