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A001809 as a simple table

na(n)
00
10
21
39
472
5600
65400
752920
8564480
96531840
1081648000
111097712000
1215807052800
13242853811200
143966612249600
1568652904320000
161255367393280000
1724186745110528000
18489781588488192000
1910400656084955136000
20231125690776780800000
215364548928029491200000

[0,0,1,9,72,600,5400,52920,564480,6531840,
 81648000,1097712000,15807052800,242853811200,
 3966612249600,68652904320000,1255367393280000,
 24186745110528000,489781588488192000,
 10400656084955136000,231125690776780800000,
 5364548928029491200000]