A189867 - OEIS

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A189867 as a simple table

n	a(n)
1	1
2	0
3	0
4	2
5	10
6	0
7	0
8	0
9	0
10	48
11	152
12	472
13	2696
14	12320
15	74436
16	429620
17	2515116
18	16122496
19	113016608
20	843492920
21	6575649316
22	54694203188

[1,0,0,2,10,0,0,0,0,48,152,472,2696,12320,74436, 429620,2515116,16122496,113016608,843492920, 6575649316,54694203188]