n | a(n) |
---|---|
1 | 4 |
2 | 10 |
3 | 20 |
4 | 55 |
5 | 136 |
6 | 430 |
7 | 1300 |
8 | 4435 |
9 | 15084 |
10 | 53764 |
11 | 192700 |
12 | 704370 |
13 | 2589304 |
14 | 9608050 |
15 | 35824240 |
16 | 134301715 |
17 | 505421344 |
18 | 1909209550 |
19 | 7234153420 |
20 | 27489127708 |
21 | 104717491064 |
22 | 399827748310 |
23 | 1529763696820 |
[4,10,20,55,136,430,1300,4435,15084,53764,192700, 704370,2589304,9608050,35824240,134301715, 505421344,1909209550,7234153420,27489127708, 104717491064,399827748310,1529763696820] |