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A002867 as a simple table

na(n)
01
12
212
372
4720
57200
6100800
71411200
825401600
9457228800
1010059033600
11221298739200
125753767219200
13149597947699200
144487938430976000
15134638152929280000
164577697199595520000
17155641704786247680000

[1,2,12,72,720,7200,100800,1411200,25401600,
 457228800,10059033600,221298739200,5753767219200,
 149597947699200,4487938430976000,
 134638152929280000,4577697199595520000,
 155641704786247680000]