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 | 21 |
| 3 | 271 |
| 4 | 5065 |
| 5 | 122811 |
| 6 | 3651997 |
| 7 | 128566663 |
| 8 | 5227782161 |
| 9 | 241072839667 |
| 10 | 12430169195941 |
| 11 | 708612945554559 |
| 12 | 44253858433505497 |
| 13 | 3004570398043291819 |
| 14 | 220341964157226260525 |
| 15 | 17357760973540312138231 |
| 16 | 1461813975265547356467745 |
| 17 | 131061164660246579394042339 |