n | a(n) |
---|---|
0 | 1 |
1 | 4 |
2 | 20 |
3 | 106 |
4 | 560 |
5 | 2914 |
6 | 14960 |
7 | 76066 |
8 | 384320 |
9 | 1933954 |
10 | 9707600 |
11 | 48653026 |
12 | 243613280 |
13 | 1219116994 |
14 | 6098749040 |
15 | 30503261986 |
16 | 152544909440 |
17 | 762810444034 |
18 | 3814310107280 |
19 | 19072324590946 |
20 | 95363945904800 |
21 | 476826699947074 |
22 | 2384154414150320 |
23 | 11920834820287906 |
24 | 59604362362631360 |
25 | 298022376621898114 |
[1,4,20,106,560,2914,14960,76066,384320,1933954, 9707600,48653026,243613280,1219116994,6098749040, 30503261986,152544909440,762810444034, 3814310107280,19072324590946,95363945904800, 476826699947074,2384154414150320, 11920834820287906,59604362362631360, 298022376621898114] |