n | a(n) |
---|---|
1 | 4 |
2 | 20 |
3 | 58 |
4 | 292 |
5 | 1235 |
6 | 5186 |
7 | 22461 |
8 | 96256 |
9 | 413032 |
10 | 1780597 |
11 | 7673860 |
12 | 33017186 |
13 | 142219489 |
14 | 612618957 |
15 | 2638803566 |
16 | 11367909928 |
17 | 48973948677 |
18 | 210982341958 |
19 | 908945163931 |
20 | 3915948771137 |
21 | 16870934284560 |
22 | 72684969189462 |
[4,20,58,292,1235,5186,22461,96256,413032,1780597, 7673860,33017186,142219489,612618957,2638803566, 11367909928,48973948677,210982341958,908945163931, 3915948771137,16870934284560,72684969189462] |