n | a(n) |
---|---|
0 | -1 |
1 | 0 |
2 | 6 |
3 | 30 |
4 | 114 |
5 | 390 |
6 | 1266 |
7 | 3990 |
8 | 12354 |
9 | 37830 |
10 | 115026 |
11 | 348150 |
12 | 1050594 |
13 | 3164070 |
14 | 9516786 |
15 | 28599510 |
16 | 85896834 |
17 | 257887110 |
18 | 774054546 |
19 | 2322950070 |
20 | 6970423074 |
21 | 20914414950 |
22 | 62749536306 |
23 | 188261191830 |
24 | 564808741314 |
25 | 1694476555590 |
26 | 5083530330066 |
27 | 15250792316790 |
[-1,0,6,30,114,390,1266,3990,12354,37830,115026, 348150,1050594,3164070,9516786,28599510,85896834, 257887110,774054546,2322950070,6970423074, 20914414950,62749536306,188261191830,564808741314, 1694476555590,5083530330066,15250792316790] |