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 | 1 |
| 2 | 3 |
| 3 | 14 |
| 4 | 73 |
| 5 | 440 |
| 6 | 2862 |
| 7 | 19991 |
| 8 | 146939 |
| 9 | 1125413 |
| 10 | 8896018 |
| 11 | 72067978 |
| 12 | 595097838 |
| 13 | 4987609871 |
| 14 | 42290465703 |
| 15 | 361845473658 |
| 16 | 3117830204185 |
| 17 | 27009650432888 |
| 18 | 234932107635587 |
| 19 | 2049479335366836 |
| 20 | 17915253987741538 |
| 21 | 156799716352350344 |
| 22 | 1373180896765862962 |