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 | 6 |
| 4 | 15 |
| 5 | 41 |
| 6 | 107 |
| 7 | 287 |
| 8 | 758 |
| 9 | 2022 |
| 10 | 5362 |
| 11 | 14276 |
| 12 | 37916 |
| 13 | 100874 |
| 14 | 268084 |
| 15 | 713006 |
| 16 | 1895415 |
| 17 | 5040433 |
| 18 | 13400863 |
| 19 | 35634419 |
| 20 | 94745705 |
| 21 | 251932417 |
| 22 | 669862581 |
| 23 | 1781165785 |
| 24 | 4736000199 |
| 25 | 12592950131 |
| 26 | 33484024019 |
| 27 | 89033206579 |
| 28 | 236735594539 |