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 | 4 |
| 3 | 10 |
| 4 | 32 |
| 5 | 126 |
| 6 | 588 |
| 7 | 3171 |
| 8 | 19382 |
| 9 | 132099 |
| 10 | 990756 |
| 11 | 8093603 |
| 12 | 71436060 |
| 13 | 676734190 |
| 14 | 6842383982 |
| 15 | 73483900031 |
| 16 | 834766518890 |
| 17 | 9994386677811 |
| 18 | 125715770020804 |
| 19 | 1656716763283342 |
| 20 | 22816308485104494 |
| 21 | 327646842078735037 |
| 22 | 4896100535018809108 |
| 23 | 75994281001001114847 |