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 | 4 |
| 2 | 7 |
| 3 | 10 |
| 4 | 13 |
| 5 | 23 |
| 6 | 40 |
| 7 | 63 |
| 8 | 176 |
| 9 | 239 |
| 10 | 329 |
| 11 | 568 |
| 12 | 10381 |
| 13 | 49128 |
| 14 | 60974 |
| 15 | 281746 |
| 16 | 342720 |
| 17 | 7484108 |
| 18 | 11452573 |
| 19 | 18936681 |
| 20 | 44390284 |
| 21 | 55842857 |