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 | 1 |
| 3 | 4 |
| 4 | 15 |
| 5 | 52 |
| 6 | 210 |
| 7 | 796 |
| 8 | 3175 |
| 9 | 12468 |
| 10 | 49288 |
| 11 | 194140 |
| 12 | 766110 |
| 13 | 3019224 |
| 14 | 11905330 |
| 15 | 46938192 |
| 16 | 185111095 |
| 17 | 730148332 |
| 18 | 2880799554 |
| 19 | 11369141308 |
| 20 | 44881708072 |
| 21 | 177229210656 |
| 22 | 700047776214 |
| 23 | 2765947680124 |
| 24 | 10931565973950 |
| 25 | 43215517211240 |
| 26 | 170888480306500 |