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 | 3 |
| 2 | 11 |
| 3 | 44 |
| 4 | 188 |
| 5 | 842 |
| 6 | 3911 |
| 7 | 18692 |
| 8 | 91412 |
| 9 | 455540 |
| 10 | 2306028 |
| 11 | 11829424 |
| 12 | 61375408 |
| 13 | 321583108 |
| 14 | 1699500055 |
| 15 | 9049714852 |
| 16 | 48513809796 |
| 17 | 261638920412 |
| 18 | 1418673379052 |
| 19 | 7730011715760 |
| 20 | 42305916178288 |
| 21 | 232475082183544 |
| 22 | 1282208011668988 |
| 23 | 7096065370945168 |
| 24 | 39394821683770960 |
| 25 | 219341739839760912 |