n | a(n) |
---|---|
0 | 1 |
1 | 1 |
2 | 3 |
3 | 7 |
4 | 20 |
5 | 54 |
6 | 164 |
7 | 500 |
8 | 1629 |
9 | 5462 |
10 | 19164 |
11 | 69457 |
12 | 261154 |
13 | 1012164 |
14 | 4045640 |
15 | 16611121 |
16 | 70001515 |
17 | 301922104 |
18 | 1331128134 |
19 | 5986321599 |
20 | 27426419974 |
21 | 127801386949 |
22 | 605016657100 |
23 | 2906093083727 |
24 | 14149469612919 |
25 | 69762426194708 |
26 | 348016146152252 |
27 | 1755188873640756 |
[1,1,3,7,20,54,164,500,1629,5462,19164,69457, 261154,1012164,4045640,16611121,70001515, 301922104,1331128134,5986321599,27426419974, 127801386949,605016657100,2906093083727, 14149469612919,69762426194708,348016146152252, 1755188873640756] |