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A226198 as a simple table

na(n)
11
20
30
41
54
620
7102
8630
94480
1036288
11329890
123326400
1336846276
14444787200
155811886080
1681729648000
171230752346352
1819760412672000
19336967037143578
206082255020441600
21115852476579840000
222322315553259520000
2348869596859895986086

[1,0,0,1,4,20,102,630,4480,36288,329890,3326400,
 36846276,444787200,5811886080,81729648000,
 1230752346352,19760412672000,336967037143578,
 6082255020441600,115852476579840000,
 2322315553259520000,48869596859895986086]