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 | 14 |
| 3 | 44 |
| 4 | 129 |
| 5 | 360 |
| 6 | 968 |
| 7 | 2528 |
| 8 | 6448 |
| 9 | 16128 |
| 10 | 39680 |
| 11 | 96256 |
| 12 | 230656 |
| 13 | 546816 |
| 14 | 1284096 |
| 15 | 2990080 |
| 16 | 6909952 |
| 17 | 15859712 |
| 18 | 36175872 |
| 19 | 82051072 |
| 20 | 185139200 |
| 21 | 415760384 |
| 22 | 929562624 |
| 23 | 2069889024 |
| 24 | 4591714304 |
| 25 | 10150215680 |
| 26 | 22364028928 |
| 27 | 49123688448 |
| 28 | 107592286208 |
| 29 | 235015241728 |
| 30 | 512040632320 |