n | a(n) |
---|---|
1 | 4 |
2 | 18 |
3 | 88 |
4 | 454 |
5 | 2424 |
6 | 13270 |
7 | 73988 |
8 | 384360 |
9 | 2126012 |
10 | 11983288 |
11 | 68380920 |
12 | 371177576 |
13 | 2103489988 |
14 | 12072527960 |
15 | 69865022356 |
16 | 389690375308 |
17 | 2242267086352 |
18 | 13018490319724 |
19 | 73199231868324 |
20 | 423255665348852 |
21 | 2467041278509640 |
[4,18,88,454,2424,13270,73988,384360,2126012, 11983288,68380920,371177576,2103489988, 12072527960,69865022356,389690375308, 2242267086352,13018490319724,73199231868324, 423255665348852,2467041278509640] |