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 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 10 |
| 5 | 26 |
| 6 | 76 |
| 7 | 231 |
| 8 | 756 |
| 9 | 2556 |
| 10 | 9096 |
| 11 | 33231 |
| 12 | 126060 |
| 13 | 488488 |
| 14 | 1948232 |
| 15 | 7907185 |
| 16 | 32831370 |
| 17 | 138321690 |
| 18 | 593610420 |
| 19 | 2579109780 |
| 20 | 11377862340 |
| 21 | 50726936820 |
| 22 | 229078351992 |
| 23 | 1043999256966 |
| 24 | 4810194384348 |
| 25 | 22340617618860 |
| 26 | 104742353862360 |
| 27 | 494547143860035 |