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 | 6 |
| 1 | 22 |
| 2 | 70 |
| 3 | 214 |
| 4 | 646 |
| 5 | 1942 |
| 6 | 5830 |
| 7 | 17494 |
| 8 | 52486 |
| 9 | 157462 |
| 10 | 472390 |
| 11 | 1417174 |
| 12 | 4251526 |
| 13 | 12754582 |
| 14 | 38263750 |
| 15 | 114791254 |
| 16 | 344373766 |
| 17 | 1033121302 |
| 18 | 3099363910 |
| 19 | 9298091734 |
| 20 | 27894275206 |
| 21 | 83682825622 |
| 22 | 251048476870 |
| 23 | 753145430614 |
| 24 | 2259436291846 |