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A121281 as a simple table

na(n)
01
12
21
36
43
52
630
715
810
96
10210
11105
1270
1342
1430
152310
161155
17770
18462
19330
20210
2130030
2215015
2310010
246006
254290
262730
272310
28510510
29255255
30170170
31102102
3272930
3346410
3439270
3530030
369699690
374849845
383233230
391939938
401385670
41881790
42746130
43570570
44510510

[1,2,1,6,3,2,30,15,10,6,210,105,70,42,30,2310,
 1155,770,462,330,210,30030,15015,10010,6006,4290,
 2730,2310,510510,255255,170170,102102,72930,46410,
 39270,30030,9699690,4849845,3233230,1939938,
 1385670,881790,746130,570570,510510]