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 | 3 |
| 3 | 14 |
| 4 | 132 |
| 5 | 691 |
| 6 | 1908 |
| 7 | 16579 |
| 8 | 47352 |
| 9 | 414301 |
| 10 | 1183713 |
| 11 | 5474669 |
| 12 | 27151397 |
| 13 | 135646011 |
| 14 | 678174568 |
| 15 | 6442602909 |
| 16 | 18480090517 |
| 17 | 85533990571 |
| 18 | 424236721848 |
| 19 | 4026815626549 |
| 20 | 11550150977337 |
| 21 | 53458791308981 |
| 22 | 265147974756053 |
| 23 | 1324666882885839 |
| 24 | 6622797918981982 |
| 25 | 62916043734881616 |
| 26 | 329481245744393933 |