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 | 2 |
| 2 | 5 |
| 3 | 10 |
| 4 | 22 |
| 5 | 48 |
| 6 | 112 |
| 7 | 274 |
| 8 | 715 |
| 9 | 1982 |
| 10 | 5837 |
| 11 | 18180 |
| 12 | 59644 |
| 13 | 205296 |
| 14 | 739032 |
| 15 | 2775180 |
| 16 | 10846965 |
| 17 | 44039754 |
| 18 | 185391469 |
| 19 | 807776198 |
| 20 | 3637193474 |
| 21 | 16900721824 |
| 22 | 80939650552 |
| 23 | 399061251246 |
| 24 | 2023408865983 |
| 25 | 10540656630118 |