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A200092 as a simple table

na(n)
31
41
51
61
720
81
970
101
11182
121
13420
141680
151
16912
1712600
181
191914
2062370
211
223938
23256410
24369600
251
268008
27949806
284804800
291
3016172
313297294
3238678640
331
3432526
3510966956
36248047800
37168168000

[1,1,1,1,20,1,70,1,182,1,420,1680,1,912,12600,1,
 1914,62370,1,3938,256410,369600,1,8008,949806,
 4804800,1,16172,3297294,38678640,1,32526,10966956,
 248047800,168168000]