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 | 10 |
| 2 | 501 |
| 3 | 5020 |
| 4 | 251501 |
| 5 | 2520030 |
| 6 | 126253001 |
| 7 | 1265050040 |
| 8 | 63378755001 |
| 9 | 635052600050 |
| 10 | 31816008757501 |
| 11 | 318795140175060 |
| 12 | 15971573017510501 |
| 13 | 160034525315280070 |
| 14 | 8017697838781514001 |
| 15 | 80337012913130420080 |
| 16 | 4024868343495302518001 |
| 17 | 40329020447866155600090 |