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 | 1 |
| 3 | 5 |
| 4 | 17 |
| 5 | 91 |
| 6 | 379 |
| 7 | 721 |
| 8 | 35849 |
| 9 | 614893 |
| 10 | 6800951 |
| 11 | 607326679 |
| 12 | 3651532639 |
| 13 | 851897554247 |
| 14 | 24724573280923 |
| 15 | 301787157353771 |
| 16 | 14188276949397301 |
| 17 | 22662903194758542865 |
| 18 | 430644772287132696121 |
| 19 | 1800653989272587268758525 |
| 20 | 369150309888695460837999593 |