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 | 1 |
| 2 | 2047 |
| 3 | 88573 |
| 4 | 2794155 |
| 5 | 12207031 |
| 6 | 181308931 |
| 7 | 329554457 |
| 8 | 3269560515 |
| 9 | 5883904390 |
| 10 | 24987792457 |
| 11 | 28531167061 |
| 12 | 247486690815 |
| 13 | 149346699503 |
| 14 | 674597973479 |
| 15 | 1081213356763 |
| 16 | 3571013994483 |
| 17 | 2141993519227 |
| 18 | 12044352286330 |
| 19 | 6471681049901 |
| 20 | 34108336703805 |
| 21 | 29189626919861 |