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A137668 as a simple table

na(n)
10
21
30
4-2
50
62
70
824
90
10-40
110
1216
130
14-720
150
161568
170
18-1120
190
20272
210
2240320
230
24-104704
250
26102144
270
28-45696
290
307936
310
32-3628800
330
3410720512
350
36-12869120
370
388042496
390
40-2618880
410
42353792
430
44479001600
450
46-1565051904
470
482188865536
490
50-1712668672
510
52789854208
530
54-202369024
550

[0,1,0,-2,0,2,0,24,0,-40,0,16,0,-720,0,1568,0,
 -1120,0,272,0,40320,0,-104704,0,102144,0,-45696,0,
 7936,0,-3628800,0,10720512,0,-12869120,0,8042496,
 0,-2618880,0,353792,0,479001600,0,-1565051904,0,
 2188865536,0,-1712668672,0,789854208,0,-202369024,
 0]