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%I #8 Oct 30 2012 16:51:04
%S 4,90,560,4032,302400,34214400,415134720,5448643200,1162377216000,
%T 320118685286400,5792623828992000,110586454917120000,
%U 46833363657400320000,1034080669555399065600,23863400066663055360000,574489260864110592000000,14403266468807344128000000,10162944820390462016716800000
%N (n-2)!/n when an integer.
%C n divides (n-2)! for all composite n >= 6.
%e a(1) = 4 because 4!/6 = 4. That is, 6 divides 4!.
%e a(2) =90 because the next composite number after 6 is 8. 6!/8 = 90, which means 8 divides 6!
%t f[n_] := If[PrimeQ[n], 0, (n-2)!/n]; Select[Table[f[n], {n,30}], IntegerQ[#] && #>0&]
%Y Cf. A129906.
%K nonn
%O 1,1
%A _Geoffrey Critzer_, Oct 27 2012
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