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A228955 as a simple table

na(n)
01
11
21
32
46
56
636
76
824
9240
10120
11120
121800
131800
14120
15720
1615120
1725200
185040
195040
20141120
21352800
22141120
235040
2440320
251451520
265080320
273386880
28362880
29362880
3016329600
3176204800
3276204800
3316329600
34362880
353628800
36199584000
371197504000
381676505600
39598752000
4039916800

[1,1,1,2,6,6,36,6,24,240,120,120,1800,1800,120,
 720,15120,25200,5040,5040,141120,352800,141120,
 5040,40320,1451520,5080320,3386880,362880,362880,
 16329600,76204800,76204800,16329600,362880,
 3628800,199584000,1197504000,1676505600,598752000,
 39916800]