n | a(n) |
---|---|
0 | 1 |
1 | 4 |
2 | 20 |
3 | 130 |
4 | 1088 |
5 | 11314 |
6 | 141080 |
7 | 2052250 |
8 | 34118048 |
9 | 638102434 |
10 | 13260323240 |
11 | 303117147370 |
12 | 7558845354608 |
13 | 204203189722354 |
14 | 5940927689713400 |
15 | 185186461979970490 |
16 | 6157337034085736768 |
17 | 217523186522883467074 |
18 | 8136577601614291359560 |
19 | 321261794453042025993610 |
20 | 13352198666907246870560528 |
[1,4,20,130,1088,11314,141080,2052250,34118048, 638102434,13260323240,303117147370,7558845354608, 204203189722354,5940927689713400, 185186461979970490,6157337034085736768, 217523186522883467074,8136577601614291359560, 321261794453042025993610, 13352198666907246870560528] |