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 | 18 |
| 3 | 147 |
| 4 | 996 |
| 5 | 6245 |
| 6 | 37494 |
| 7 | 218743 |
| 8 | 1249992 |
| 9 | 7031241 |
| 10 | 39062490 |
| 11 | 214843739 |
| 12 | 1171874988 |
| 13 | 6347656237 |
| 14 | 34179687486 |
| 15 | 183105468735 |
| 16 | 976562499984 |
| 17 | 5187988281233 |
| 18 | 27465820312482 |
| 19 | 144958496093731 |
| 20 | 762939453124980 |