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%I #11 Mar 06 2017 17:20:09
%S 125,1255,2510,11009,11099,11255,11379,12326,12955,14379,14397,15033,
%T 15303,16325,17482,21109,25105,31007,31503,33011,35213,37127,37921,
%U 41303,44011,49319,51367,53491,63013,69413,70319,71057,72013,72517,74341,77011,81767
%N Composite numbers n such that the distinct digits in n and the distinct digits in the proper divisors of n are the same.
%C Since 1 is always a divisor of n, this is a subsequence of A011531. - _Michel Marcus_, Feb 12 2014
%H Giovanni Resta, <a href="/A237713/b237713.txt">Table of n, a(n) for n = 1..10000</a>
%e 125 is in the sequence because the proper divisors of 125 are {1, 5, 25} with the same digits as 125.
%t Pn[n_]:=Sort[DeleteDuplicates[Flatten[IntegerDigits[Take[Divisors[n],DivisorSigma[0,n]-1]]]]];Fn[n_]:=Sort[DeleteDuplicates[IntegerDigits[n]]];lst={};Do[If[!PrimeQ[n]&&Pn[n]===Fn[n],AppendTo[lst,n]],{n,2,10^5}];lst
%t Select[Range[10^5], ! PrimeQ@# && Union@ IntegerDigits@ # == Union @@ IntegerDigits /@ Most@ Divisors@ # &] (* _Giovanni Resta_, Feb 12 2014 *)
%o (PARI) isok(n) = { my(digs = []); fordiv(n, d, if (d != n, digs = concat(digs, digits(d)))); (n != 1) && !isprime(n) && vecsort(digs,,8) == vecsort(digits(n),,8);} \\ _Michel Marcus_, Feb 12 2014
%Y Cf. A032741, A035141.
%Y See A282755 for a variant.
%K nonn,base
%O 1,1
%A _Michel Lagneau_, Feb 12 2014
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