n | a(n) |
---|---|
0 | 1 |
1 | 6 |
2 | 24 |
3 | 90 |
4 | 336 |
5 | 1266 |
6 | 4824 |
7 | 18570 |
8 | 72096 |
9 | 281826 |
10 | 1107624 |
11 | 4371450 |
12 | 17308656 |
13 | 68703186 |
14 | 273218424 |
15 | 1088090730 |
16 | 4338014016 |
17 | 17309009346 |
18 | 69106897224 |
19 | 276040168410 |
20 | 1102998412176 |
21 | 4408506864306 |
22 | 17623567104024 |
23 | 70462887356490 |
[1,6,24,90,336,1266,4824,18570,72096,281826, 1107624,4371450,17308656,68703186,273218424, 1088090730,4338014016,17309009346,69106897224, 276040168410,1102998412176,4408506864306, 17623567104024,70462887356490] |