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A308506 as a simple table

na(n)
0-1
12
20
324
4256
55280
6129024
73893120
8138215424
95657154048
10262183321600
1113572739749888
12776265384591360
1348609716407476224
143307818108252585984
15243052603284860928000
1619179014510218162733056
171617564760662882792898560
18145212699111541646687207424

[-1,2,0,24,256,5280,129024,3893120,138215424,
 5657154048,262183321600,13572739749888,
 776265384591360,48609716407476224,
 3307818108252585984,243052603284860928000,
 19179014510218162733056,1617564760662882792898560,
 145212699111541646687207424]