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A001464 as a simple table

na(n)
01
1-1
20
32
4-2
5-6
616
720
8-132
9-28
101216
11-936
12-12440
1323672
14138048
15-469456
16-1601264
179112560
1818108928
19-182135008
20-161934624
213804634784
22-404007680
23-83297957568
2492590134208
251906560847424
26-4221314202624
27-45349267830400
28159324751301248

[1,-1,0,2,-2,-6,16,20,-132,-28,1216,-936,-12440,
 23672,138048,-469456,-1601264,9112560,18108928,
 -182135008,-161934624,3804634784,-404007680,
 -83297957568,92590134208,1906560847424,
 -4221314202624,-45349267830400,159324751301248]