n | a(n) |
---|---|
0 | 1 |
1 | 2 |
2 | 4 |
3 | 10 |
4 | 34 |
5 | 148 |
6 | 786 |
7 | 4920 |
8 | 35446 |
9 | 288822 |
10 | 2625844 |
11 | 26349340 |
12 | 289248224 |
13 | 3447860798 |
14 | 44348374106 |
15 | 612228009210 |
16 | 9028698146956 |
17 | 141655958846642 |
18 | 2355980548168314 |
19 | 41403643674710280 |
20 | 766627753698325214 |
[1,2,4,10,34,148,786,4920,35446,288822,2625844, 26349340,289248224,3447860798,44348374106, 612228009210,9028698146956,141655958846642, 2355980548168314,41403643674710280, 766627753698325214] |