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A002539 as a simple table

na(n)
01
122
2328
34400
458140
5785304
611026296
7162186912
82507481216
940788301824
10697929436800
1112550904017920
12236908271543040
134687098165573120
1497049168010017280
152099830209402931200
1647405948832458496000
171115089078488795648000
1827290469545695931904000
19694002594415741341696000

[1,22,328,4400,58140,785304,11026296,162186912,
 2507481216,40788301824,697929436800,
 12550904017920,236908271543040,4687098165573120,
 97049168010017280,2099830209402931200,
 47405948832458496000,1115089078488795648000,
 27290469545695931904000,694002594415741341696000]