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A139550 as a simple table

na(n)
01
11
21
31
42
52
66
76
812
912
1060
1160
1260
1360
14420
15420
16840
17840
182520
192520
202520
212520
2227720
2327720
2427720
2527720
26360360
27360360
28360360
29360360
30360360
31360360
32720720
33720720
3412252240
3512252240
3612252240
3712252240
38232792560
39232792560

[1,1,1,1,2,2,6,6,12,12,60,60,60,60,420,420,840,
 840,2520,2520,2520,2520,27720,27720,27720,27720,
 360360,360360,360360,360360,360360,360360,720720,
 720720,12252240,12252240,12252240,12252240,
 232792560,232792560]