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Largest composite number formed by permuting the digits of n, or 0 if no such number exists.
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%I #6 Feb 14 2016 08:53:14

%S 0,0,0,4,0,6,0,8,9,10,0,21,0,14,51,16,0,81,91,20,21,22,32,42,52,62,72,

%T 82,92,30,0,32,33,34,35,63,0,38,93,40,14,42,34,44,54,64,74,84,94,50,

%U 51,52,35,54,55,65,75,85,95,60,16,62,63,64,65,66,76,86,96,70,0,72,0,74,75

%N Largest composite number formed by permuting the digits of n, or 0 if no such number exists.

%t Table[Max[Select[FromDigits/@Permutations[IntegerDigits[n]], CompositeQ]],{n,80}]/.(-\[Infinity]->0) (* _Harvey P. Dale_, Feb 14 2016 *)

%Y Cf. A047814.

%K easy,nonn,base

%O 1,4

%A _Amarnath Murthy_, Sep 11 2002

%E More terms from _David Wasserman_, Jan 16 2005