n | a(n) |
---|---|
1 | 0 |
2 | 1 |
3 | 3 |
4 | 9 |
5 | 26 |
6 | 74 |
7 | 209 |
8 | 588 |
9 | 1651 |
10 | 4631 |
11 | 12983 |
12 | 36388 |
13 | 101972 |
14 | 285741 |
15 | 800660 |
16 | 2243445 |
17 | 6286059 |
18 | 17613241 |
19 | 49351342 |
20 | 138279586 |
21 | 387451077 |
22 | 1085614208 |
23 | 3041824015 |
24 | 8523002359 |
25 | 23880923183 |
26 | 66912861640 |
27 | 187485674652 |
28 | 525323190505 |
29 | 1471922876424 |
30 | 4124236259529 |
[0,1,3,9,26,74,209,588,1651,4631,12983,36388, 101972,285741,800660,2243445,6286059,17613241, 49351342,138279586,387451077,1085614208, 3041824015,8523002359,23880923183,66912861640, 187485674652,525323190505,1471922876424, 4124236259529] |