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 | 1 |
| 2 | 6 |
| 3 | 13 |
| 4 | 71 |
| 5 | 439 |
| 6 | 510 |
| 7 | 2455069 |
| 8 | 2455579 |
| 9 | 4910648 |
| 10 | 12276875 |
| 11 | 29464398 |
| 12 | 71205671 |
| 13 | 100670069 |
| 14 | 171875740 |
| 15 | 272545809 |
| 16 | 1807150594 |
| 17 | 9308298779 |
| 18 | 11115449373 |
| 19 | 931890596738 |
| 20 | 6534349626539 |
| 21 | 14000589849816 |
| 22 | 20534939476355 |
| 23 | 34535529326171 |
| 24 | 55070468802526 |
| 25 | 475099279746379 |
| 26 | 2430566867534421 |