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 | 6 |
| 2 | 24 |
| 3 | 100 |
| 4 | 396 |
| 5 | 1596 |
| 6 | 6364 |
| 7 | 25500 |
| 8 | 101916 |
| 9 | 407836 |
| 10 | 1631004 |
| 11 | 6524700 |
| 12 | 26097436 |
| 13 | 104392476 |
| 14 | 417564444 |
| 15 | 1670268700 |
| 16 | 6681052956 |
| 17 | 26724255516 |
| 18 | 106896934684 |
| 19 | 427587913500 |
| 20 | 1710351304476 |
| 21 | 6841405916956 |
| 22 | 27365622269724 |
| 23 | 109462491875100 |
| 24 | 437849961907996 |
| 25 | 1751399858816796 |
| 26 | 7005599412897564 |
| 27 | 28022397696329500 |
| 28 | 112089590695839516 |