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A180874 as a simple table

na(n)
11
21
35
456
51092
632670
71387815
879389310
95882844968
10548129834616
1162720089624920
128646340208462880
131413380381699497200
14270316008395632253340
1559800308109377016336155
1615151722444639718679892150
174359147487054262623576455600

[1,1,5,56,1092,32670,1387815,79389310,5882844968,
 548129834616,62720089624920,8646340208462880,
 1413380381699497200,270316008395632253340,
 59800308109377016336155,
 15151722444639718679892150,
 4359147487054262623576455600]