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 | 12 |
| 3 | 34 |
| 4 | 98 |
| 5 | 294 |
| 6 | 919 |
| 7 | 2974 |
| 8 | 9891 |
| 9 | 33604 |
| 10 | 116103 |
| 11 | 406614 |
| 12 | 1440025 |
| 13 | 5147876 |
| 14 | 18550572 |
| 15 | 67310938 |
| 16 | 245716094 |
| 17 | 901759950 |
| 18 | 3325066996 |
| 19 | 12312494462 |
| 20 | 45766188948 |
| 21 | 170702447074 |
| 22 | 638698318850 |
| 23 | 2396598337950 |