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) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 10 |
| 5 | 24 |
| 6 | 63 |
| 7 | 166 |
| 8 | 471 |
| 9 | 1408 |
| 10 | 4436 |
| 11 | 14719 |
| 12 | 51468 |
| 13 | 188754 |
| 14 | 725010 |
| 15 | 2907576 |
| 16 | 12141462 |
| 17 | 52654529 |
| 18 | 236584104 |
| 19 | 1098926868 |
| 20 | 5266708497 |
| 21 | 25997964452 |
| 22 | 131975740172 |
| 23 | 688019138485 |
| 24 | 3678898458587 |
| 25 | 20153878941460 |
| 26 | 113000861804642 |
| 27 | 647866385202660 |
| 28 | 3794917399892511 |
| 29 | 22693153274994534 |
| 30 | 138436809489370914 |
| 31 | 860962282687080614 |