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A208649 as a simple table

na(n)
11
21
31
43
56
640
7150
82100
914700
10423360
115556600
12325987200
138068183200
14958961203200
1544996257706400
1610799101849536000
17965169727802280000
18466713183932835840000
1979775138681769651120000

[1,1,1,3,6,40,150,2100,14700,423360,5556600,
 325987200,8068183200,958961203200,44996257706400,
 10799101849536000,965169727802280000,
 466713183932835840000,79775138681769651120000]