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 | 1 |
| 2 | 10 |
| 3 | 141 |
| 4 | 2776 |
| 5 | 70045 |
| 6 | 2157156 |
| 7 | 78452521 |
| 8 | 3290644288 |
| 9 | 156380715801 |
| 10 | 8304267312100 |
| 11 | 487328231729581 |
| 12 | 31318669850761008 |
| 13 | 2187567259278425557 |
| 14 | 165011952533314548676 |
| 15 | 13368463736048341225425 |
| 16 | 1157693100510102752463616 |
| 17 | 106719312722496774534400177 |
| 18 | 10433609651067618426072766020 |