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 | 4 |
| 3 | 12 |
| 4 | 43 |
| 5 | 134 |
| 6 | 448 |
| 7 | 1387 |
| 8 | 4347 |
| 9 | 13128 |
| 10 | 39350 |
| 11 | 115285 |
| 12 | 334179 |
| 13 | 952512 |
| 14 | 2684714 |
| 15 | 7468402 |
| 16 | 20556838 |
| 17 | 55963935 |
| 18 | 150896053 |
| 19 | 402999801 |
| 20 | 1066962557 |
| 21 | 2801089402 |
| 22 | 7295920768 |
| 23 | 18859954024 |
| 24 | 48404773852 |
| 25 | 123381167011 |
| 26 | 312438704848 |
| 27 | 786231143489 |
| 28 | 1966628476977 |