Erroneous version of A056218.

Terms

a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =60a(6) =1a(7) =5040a(8) =10080a(9) =15120a(10) =1a(11) =19958400a(12) =1a(13) =8648640a(14) =1816214400a(16) =1a(18) =1a(22) =1