n | a(n) |
---|---|
0 | 0 |
1 | 2 |
2 | 2 |
3 | 12 |
4 | 68 |
5 | 780 |
6 | 7782 |
7 | 137256 |
8 | 2130440 |
9 | 47895390 |
10 | 1010001010 |
11 | 28531167060 |
12 | 743044451340 |
13 | 25239592216020 |
14 | 797785000011174 |
15 | 31147773583410240 |
16 | 1157442765409226768 |
17 | 51702516367896047760 |
18 | 2185932446972586391986 |
19 | 109912203092239643840220 |
20 | 5255987282125313280008020 |
[0,2,2,12,68,780,7782,137256,2130440,47895390, 1010001010,28531167060,743044451340, 25239592216020,797785000011174,31147773583410240, 1157442765409226768,51702516367896047760, 2185932446972586391986,109912203092239643840220, 5255987282125313280008020] |