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 | 1 |
| 2 | 2 |
| 3 | 12 |
| 4 | 31 |
| 5 | 211 |
| 6 | 552 |
| 7 | 3782 |
| 8 | 9901 |
| 9 | 67861 |
| 10 | 177662 |
| 11 | 1217712 |
| 12 | 3188011 |
| 13 | 21850951 |
| 14 | 57206532 |
| 15 | 392099402 |
| 16 | 1026529561 |
| 17 | 7035938281 |
| 18 | 18420325562 |
| 19 | 126254789652 |
| 20 | 330539330551 |
| 21 | 2265550275451 |
| 22 | 5931287624352 |
| 23 | 40653650168462 |
| 24 | 106432637907781 |
| 25 | 729500152756861 |