n | a(n) |
---|---|
0 | 1 |
1 | 2 |
2 | 6 |
3 | 20 |
4 | 72 |
5 | 272 |
6 | 1064 |
7 | 4272 |
8 | 17504 |
9 | 72896 |
10 | 307648 |
11 | 1312896 |
12 | 5655808 |
13 | 24562176 |
14 | 107419264 |
15 | 472675072 |
16 | 2091206144 |
17 | 9296612352 |
18 | 41507566592 |
19 | 186045061120 |
20 | 836830457856 |
21 | 3776131489792 |
22 | 17089399689216 |
23 | 77548125675520 |
24 | 352766964908032 |
[1,2,6,20,72,272,1064,4272,17504,72896,307648, 1312896,5655808,24562176,107419264,472675072, 2091206144,9296612352,41507566592,186045061120, 836830457856,3776131489792,17089399689216, 77548125675520,352766964908032] |