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 | 5 |
| 2 | 52 |
| 3 | 521 |
| 4 | 526 |
| 5 | 5213 |
| 6 | 52651 |
| 7 | 52187 |
| 8 | 526093 |
| 9 | 5213591 |
| 10 | 5265679 |
| 11 | 52182884 |
| 12 | 526041442 |
| 13 | 5213070221 |
| 14 | 5265153016 |
| 15 | 52187571503 |
| 16 | 526098785251 |
| 17 | 521354939267 |
| 18 | 5265627964183 |
| 19 | 52182368437091 |
| 20 | 52604613476359 |
| 21 | 521302851738674 |