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 | 2 |
| 1 | 7 |
| 2 | 47 |
| 3 | 322 |
| 4 | 2207 |
| 5 | 15127 |
| 6 | 103682 |
| 7 | 710647 |
| 8 | 4870847 |
| 9 | 33385282 |
| 10 | 228826127 |
| 11 | 1568397607 |
| 12 | 10749957122 |
| 13 | 73681302247 |
| 14 | 505019158607 |
| 15 | 3461452808002 |
| 16 | 23725150497407 |
| 17 | 162614600673847 |
| 18 | 1114577054219522 |
| 19 | 7639424778862807 |
| 20 | 52361396397820127 |
| 21 | 358890350005878082 |
| 22 | 2459871053643326447 |