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 | 6 |
| 2 | 40 |
| 3 | 238 |
| 4 | 1392 |
| 5 | 8118 |
| 6 | 47320 |
| 7 | 275806 |
| 8 | 1607520 |
| 9 | 9369318 |
| 10 | 54608392 |
| 11 | 318281038 |
| 12 | 1855077840 |
| 13 | 10812186006 |
| 14 | 63018038200 |
| 15 | 367296043198 |
| 16 | 2140758220992 |
| 17 | 12477253282758 |
| 18 | 72722761475560 |
| 19 | 423859315570606 |
| 20 | 2470433131948080 |
| 21 | 14398739476117878 |
| 22 | 83922003724759192 |