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A001813 as a simple table

na(n)
01
12
212
3120
41680
530240
6665280
717297280
8518918400
917643225600
10670442572800
1128158588057600
121295295050649600
1364764752532480000
143497296636753920000
15202843204931727360000
1612576278705767096320000
17830034394580628357120000
1858102407620643984998400000

[1,2,12,120,1680,30240,665280,17297280,518918400,
 17643225600,670442572800,28158588057600,
 1295295050649600,64764752532480000,
 3497296636753920000,202843204931727360000,
 12576278705767096320000,830034394580628357120000,
 58102407620643984998400000]