n | a(n) |
---|---|
0 | 0 |
1 | 1 |
2 | 4 |
3 | 15 |
4 | 52 |
5 | 175 |
6 | 576 |
7 | 1869 |
8 | 6000 |
9 | 19107 |
10 | 60460 |
11 | 190333 |
12 | 596652 |
13 | 1863745 |
14 | 5804176 |
15 | 18028755 |
16 | 55873872 |
17 | 172818243 |
18 | 533589660 |
19 | 1644921789 |
20 | 5063762220 |
21 | 15568666029 |
22 | 47811348816 |
23 | 146675181975 |
24 | 449538774048 |
25 | 1376564658525 |
[0,1,4,15,52,175,576,1869,6000,19107,60460,190333, 596652,1863745,5804176,18028755,55873872, 172818243,533589660,1644921789,5063762220, 15568666029,47811348816,146675181975,449538774048, 1376564658525] |