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A169637号作为一张简单的桌子

n个a(n)
01
11
21
4
420
560
6420
73360
815120
9151200
10831600
113326400
1243243200
13302702400
141513512000
1524216192000
16411675264000
173705077376000
1870396470144000
19703964701440000
2014783258730240000
21162615846032640000
221246721486250240000
237480328917501440000

[1,1,1,4,20,60,420,3360,15120,151200,831600,3326400,43243200,302702400,1513512000,24216192000,411675264000,3705077376000,70396470144000,703964701440000,14783258730240000,162615846032640000,1246721486250240000,7480328917501440000]