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 | 7 |
| 3 | 28 |
| 4 | 122 |
| 5 | 562 |
| 6 | 2693 |
| 7 | 13288 |
| 8 | 67064 |
| 9 | 344588 |
| 10 | 1796518 |
| 11 | 9479780 |
| 12 | 50532640 |
| 13 | 271710662 |
| 14 | 1471935235 |
| 15 | 8026070768 |
| 16 | 44015873308 |
| 17 | 242619318848 |
| 18 | 1343427572648 |
| 19 | 7469219870968 |
| 20 | 41680871386016 |
| 21 | 233373274580372 |
| 22 | 1310659959443722 |
| 23 | 7381448319246248 |
| 24 | 41678055955034962 |