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 | 5 |
| 2 | 49 |
| 3 | 502 |
| 4 | 4996 |
| 5 | 49972 |
| 6 | 499986 |
| 7 | 5000046 |
| 8 | 50000675 |
| 9 | 500001223 |
| 10 | 4999997671 |
| 11 | 50000001587 |
| 12 | 500000050701 |
| 13 | 5000000008159 |
| 14 | 50000000316237 |
| 15 | 500000000977421 |
| 16 | 4999999994637728 |
| 17 | 49999999977479348 |
| 18 | 499999999944465105 |
| 19 | 4999999999725703450 |
| 20 | 49999999999090850760 |