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 | 2 |
| 1 | 5 |
| 2 | 23 |
| 3 | 103 |
| 4 | 419 |
| 5 | 1543 |
| 6 | 5519 |
| 7 | 19289 |
| 8 | 65687 |
| 9 | 220861 |
| 10 | 733561 |
| 11 | 2412779 |
| 12 | 7867547 |
| 13 | 25485211 |
| 14 | 82064027 |
| 15 | 262960091 |
| 16 | 839001721 |
| 17 | 2666790167 |
| 18 | 8448283757 |
| 19 | 26684834641 |
| 20 | 84064182061 |
| 21 | 264194301347 |
| 22 | 828513359549 |
| 23 | 2593131866483 |
| 24 | 8101615860589 |
| 25 | 25270000074757 |
| 26 | 78701296245541 |
| 27 | 244766272211729 |
| 28 | 760254097357847 |
| 29 | 2358539553316997 |