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 | 0 |
| 2 | 150 |
| 3 | 2974 |
| 4 | 2443 |
| 5 | 62158 |
| 6 | 55946694 |
| 7 | 2710261050 |
| 8 | 555008010 |
| 9 | 1547031 |
| 10 | 46165377746 |
| 11 | 95396546 |
| 12 | 92180471494910 |
| 13 | 1665088321801550 |
| 14 | 364125780 |
| 15 | 771601497990 |
| 16 | 518283023 |
| 17 | 8242065051309594 |
| 18 | 32530503217194 |
| 19 | 272602401466814027806 |
| 20 | 5568053048227732238014 |
| 21 | 85526725052226871 |