n | a(n) |
---|---|
1 | 2 |
2 | 4 |
3 | 13 |
4 | 40 |
5 | 131 |
6 | 455 |
7 | 1611 |
8 | 5818 |
9 | 21328 |
10 | 78965 |
11 | 294721 |
12 | 1107257 |
13 | 4182655 |
14 | 15873631 |
15 | 60485153 |
16 | 231287810 |
17 | 887184904 |
18 | 3412621088 |
19 | 13159857176 |
20 | 50862414259 |
21 | 196984720481 |
22 | 764321821293 |
23 | 2970680947542 |
24 | 11563991293971 |
25 | 45079009826426 |
[2,4,13,40,131,455,1611,5818,21328,78965,294721, 1107257,4182655,15873631,60485153,231287810, 887184904,3412621088,13159857176,50862414259, 196984720481,764321821293,2970680947542, 11563991293971,45079009826426] |