n | a(n) |
---|---|
0 | 1 |
1 | 1 |
2 | 3 |
3 | 12 |
4 | 57 |
5 | 312 |
6 | 1950 |
7 | 13848 |
8 | 111069 |
9 | 998064 |
10 | 9957186 |
11 | 109305240 |
12 | 1309637274 |
13 | 17006109072 |
14 | 237888664572 |
15 | 3566114897520 |
16 | 57030565449765 |
17 | 969154436550240 |
18 | 17439499379433690 |
19 | 331268545604793240 |
20 | 6624013560942038670 |
21 | 139080391965533653200 |
22 | 3059323407592802838180 |
23 | 70355685298375014175440 |
[1,1,3,12,57,312,1950,13848,111069,998064,9957186, 109305240,1309637274,17006109072,237888664572, 3566114897520,57030565449765,969154436550240, 17439499379433690,331268545604793240, 6624013560942038670,139080391965533653200, 3059323407592802838180,70355685298375014175440] |