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 | 3 |
| 2 | 15 |
| 3 | 118 |
| 4 | 1287 |
| 5 | 17547 |
| 6 | 279742 |
| 7 | 5006016 |
| 8 | 98012094 |
| 9 | 2064544861 |
| 10 | 46251043536 |
| 11 | 1092948858498 |
| 12 | 27078465176915 |
| 13 | 700154717998512 |
| 14 | 18825830520559743 |
| 15 | 524889708138232101 |
| 16 | 15140268414007624623 |
| 17 | 450944670503507069127 |