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Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A223522 as a simple table

na(n)
11
220
31
4780
560
61
745240
84320
9120
101
113483480
12382200
1313800
14200
151
16334414080
1740556880
181734600
1933600
20300
211
2238457619200
235039012160
24243505080
255699400
2669300
27420
281

[1,20,1,780,60,1,45240,4320,120,1,3483480,382200,
 13800,200,1,334414080,40556880,1734600,33600,300,
 1,38457619200,5039012160,243505080,5699400,69300,
 420,1]