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A117156 as a simple table

na(n)
01
11
22
36
423
5110
6630
74210
832150
9276210
102636720
1127687440
12317169270
133936056080
1452603684760
15753241509900
1611504852242400
17186705357825800
183208160592252000
1958188413286031600
201110946958902609400

[1,1,2,6,23,110,630,4210,32150,276210,2636720,
 27687440,317169270,3936056080,52603684760,
 753241509900,11504852242400,186705357825800,
 3208160592252000,58188413286031600,
 1110946958902609400]