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 | 0 |
| 2 | 13 |
| 3 | 7 |
| 4 | 72 |
| 5 | 255 |
| 6 | 955 |
| 7 | 3569 |
| 8 | 15031 |
| 9 | 61046 |
| 10 | 253624 |
| 11 | 1067751 |
| 12 | 4492809 |
| 13 | 18851449 |
| 14 | 79305038 |
| 15 | 333393642 |
| 16 | 1401954916 |
| 17 | 5897152044 |
| 18 | 24806594547 |
| 19 | 104353275618 |
| 20 | 439007735235 |
| 21 | 1846879331358 |
| 22 | 7769846838226 |
| 23 | 32688195410797 |
| 24 | 137521855214717 |