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 | 13 |
| 3 | 87 |
| 4 | 539 |
| 5 | 2483 |
| 6 | 14567 |
| 7 | 81669 |
| 8 | 402187 |
| 9 | 2089413 |
| 10 | 10344053 |
| 11 | 49065413 |
| 12 | 232941293 |
| 13 | 1092284091 |
| 14 | 5011510213 |
| 15 | 22637050383 |
| 16 | 100092546203 |
| 17 | 439274499155 |
| 18 | 1888145728847 |
| 19 | 8058486875493 |
| 20 | 33954688300771 |
| 21 | 140741748208701 |
| 22 | 579404121062837 |
| 23 | 2354567807958773 |
| 24 | 9481400353625789 |