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 | 43 |
| 3 | 451 |
| 4 | 4945 |
| 5 | 54685 |
| 6 | 605707 |
| 7 | 6710971 |
| 8 | 74358721 |
| 9 | 823915861 |
| 10 | 9129240139 |
| 11 | 101154812563 |
| 12 | 1120826772817 |
| 13 | 12419109262381 |
| 14 | 137607593744107 |
| 15 | 1524734943844939 |
| 16 | 16894537473570817 |
| 17 | 187196730554444581 |
| 18 | 2074198005431257579 |
| 19 | 22982759116542299875 |