n | a(n) |
---|---|
0 | 1 |
1 | 2 |
2 | 15 |
3 | 126 |
4 | 1211 |
5 | 12544 |
6 | 136668 |
7 | 1543696 |
8 | 17914325 |
9 | 212308682 |
10 | 2558783193 |
11 | 31265632206 |
12 | 386430721728 |
13 | 4822586987324 |
14 | 60686262591525 |
15 | 769167948066520 |
16 | 9810280980482827 |
17 | 125819903217235130 |
18 | 1621648696092783746 |
19 | 20993171222948561746 |
20 | 272848383910348808089 |
[1,2,15,126,1211,12544,136668,1543696,17914325, 212308682,2558783193,31265632206,386430721728, 4822586987324,60686262591525,769167948066520, 9810280980482827,125819903217235130, 1621648696092783746,20993171222948561746, 272848383910348808089] |