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 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 4 |
| 5 | 10 |
| 6 | 31 |
| 7 | 94 |
| 8 | 303 |
| 9 | 986 |
| 10 | 3284 |
| 11 | 11099 |
| 12 | 38024 |
| 13 | 131694 |
| 14 | 460607 |
| 15 | 1624451 |
| 16 | 5771532 |
| 17 | 20640334 |
| 18 | 74246701 |
| 19 | 268478962 |
| 20 | 975436348 |
| 21 | 3559204700 |
| 22 | 13037907692 |
| 23 | 47931423574 |
| 24 | 176792821643 |
| 25 | 654078238224 |
| 26 | 2426705590840 |
| 27 | 9026907769955 |