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 | 3 |
| 3 | 5 |
| 4 | 19 |
| 5 | 74 |
| 6 | 209 |
| 7 | 572 |
| 8 | 1479 |
| 9 | 4304 |
| 10 | 13002 |
| 11 | 38315 |
| 12 | 109651 |
| 13 | 308982 |
| 14 | 884120 |
| 15 | 2560952 |
| 16 | 7428183 |
| 17 | 21413028 |
| 18 | 61433280 |
| 19 | 176415916 |
| 20 | 507985116 |
| 21 | 1464725431 |
| 22 | 4220293147 |
| 23 | 12145885239 |
| 24 | 34945690653 |
| 25 | 100586823613 |
| 26 | 289649303130 |
| 27 | 834087280681 |
| 28 | 2401368817168 |
| 29 | 6912685066843 |