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 | 2 |
| 2 | 2 |
| 3 | 5 |
| 4 | 13 |
| 5 | 37 |
| 6 | 108 |
| 7 | 332 |
| 8 | 1042 |
| 9 | 3360 |
| 10 | 11019 |
| 11 | 36722 |
| 12 | 123875 |
| 13 | 422449 |
| 14 | 1453553 |
| 15 | 5040816 |
| 16 | 17599468 |
| 17 | 61814275 |
| 18 | 218252584 |
| 19 | 774226549 |
| 20 | 2758043727 |
| 21 | 9862357697 |
| 22 | 35387662266 |
| 23 | 127374191687 |
| 24 | 459783039109 |
| 25 | 1664042970924 |
| 26 | 6037070913558 |
| 27 | 21951214425140 |
| 28 | 79981665585029 |