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 | 3 |
| 2 | 4 |
| 3 | 7 |
| 4 | 25 |
| 5 | 357 |
| 6 | 1096 |
| 7 | 1453 |
| 8 | 2549 |
| 9 | 9100 |
| 10 | 129949 |
| 11 | 398947 |
| 12 | 528896 |
| 13 | 927843 |
| 14 | 3312425 |
| 15 | 47301793 |
| 16 | 145217804 |
| 17 | 192519597 |
| 18 | 337737401 |
| 19 | 1205731800 |
| 20 | 17217982601 |
| 21 | 52859679603 |
| 22 | 70077662204 |
| 23 | 122937341807 |
| 24 | 438889687625 |
| 25 | 6267392968557 |
| 26 | 19241068593296 |
| 27 | 25508461561853 |