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 | 3 |
| 2 | 9 |
| 3 | 28 |
| 4 | 87 |
| 5 | 276 |
| 6 | 909 |
| 7 | 3086 |
| 8 | 10879 |
| 9 | 39821 |
| 10 | 151363 |
| 11 | 597062 |
| 12 | 2442044 |
| 13 | 10342904 |
| 14 | 45301072 |
| 15 | 204895366 |
| 16 | 955661003 |
| 17 | 4590214994 |
| 18 | 22675644514 |
| 19 | 115068710553 |
| 20 | 599149303234 |
| 21 | 3197694533771 |
| 22 | 17475917252052 |
| 23 | 97712883807625 |
| 24 | 558481251055893 |
| 25 | 3260409769087068 |