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 | 4 |
| 3 | 11 |
| 4 | 36 |
| 5 | 117 |
| 6 | 393 |
| 7 | 1339 |
| 8 | 4630 |
| 9 | 16193 |
| 10 | 57201 |
| 11 | 203799 |
| 12 | 731602 |
| 13 | 2643903 |
| 14 | 9611748 |
| 15 | 35130195 |
| 16 | 129018798 |
| 17 | 475907913 |
| 18 | 1762457595 |
| 19 | 6550726731 |
| 20 | 24428808690 |
| 21 | 91377474411 |
| 22 | 342763939656 |
| 23 | 1289070060903 |
| 24 | 4859587760076 |
| 25 | 18360668311027 |
| 26 | 69514565858653 |
| 27 | 263693929034909 |