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) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 4 |
| 5 | 14 |
| 6 | 49 |
| 7 | 154 |
| 8 | 496 |
| 9 | 1520 |
| 10 | 4705 |
| 11 | 14266 |
| 12 | 43384 |
| 13 | 130844 |
| 14 | 394849 |
| 15 | 1187614 |
| 16 | 3571936 |
| 17 | 10729040 |
| 18 | 32222785 |
| 19 | 96724306 |
| 20 | 290313064 |
| 21 | 871172324 |
| 22 | 2614069249 |
| 23 | 7843168774 |
| 24 | 23531688976 |
| 25 | 70598997560 |
| 26 | 211805640865 |
| 27 | 635432906746 |
| 28 | 1906333059544 |
| 29 | 5719063904204 |