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 | 2 |
| 3 | 4 |
| 4 | 8 |
| 5 | 18 |
| 6 | 42 |
| 7 | 102 |
| 8 | 256 |
| 9 | 658 |
| 10 | 1722 |
| 11 | 4570 |
| 12 | 12264 |
| 13 | 33212 |
| 14 | 90626 |
| 15 | 248892 |
| 16 | 687360 |
| 17 | 1907506 |
| 18 | 5316266 |
| 19 | 14873082 |
| 20 | 41751944 |
| 21 | 117567784 |
| 22 | 331979650 |
| 23 | 939807344 |
| 24 | 2666718976 |
| 25 | 7583071868 |
| 26 | 21605822594 |
| 27 | 61672362872 |
| 28 | 176338826728 |
| 29 | 505001067346 |
| 30 | 1448365610778 |
| 31 | 4159725843526 |
| 32 | 11962301199744 |