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 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 14 |
| 5 | 42 |
| 6 | 134 |
| 7 | 444 |
| 8 | 1518 |
| 9 | 5318 |
| 10 | 18989 |
| 11 | 68856 |
| 12 | 252901 |
| 13 | 938847 |
| 14 | 3517082 |
| 15 | 13278844 |
| 16 | 50475876 |
| 17 | 193014868 |
| 18 | 741963015 |
| 19 | 2865552848 |
| 20 | 11113696421 |
| 21 | 43266626430 |
| 22 | 169019868095 |
| 23 | 662337418989 |
| 24 | 2602923589451 |
| 25 | 10256100717875 |