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%I #15 May 20 2020 16:28:11
%S 735,1255,3792,7236,11913,12955,13175,17276,17482,19075,19276,23535,
%T 25105,32104,34112,37359,42175,100255,101299,104392,105295,107329,
%U 117067,117873,121325,121904,121932,123544,123678,124483,127417,129595,131832,132565,139925
%N Composite numbers that are anagrams of the concatenation of their prime factors.
%C The sequence contains two subsequences:
%C Subsequence 1: numbers with distinct digits. This finite subsequence begins with the numbers 735, 3792, 7236, 17482, 19075, 19276, 32104, ...
%C Subsequence 2: numbers with non-distinct digits. This subsequence begins with the numbers 1255, 11913, 12955, 13175, 17276, 23535, ...
%H Robert Israel, <a href="/A306474/b306474.txt">Table of n, a(n) for n = 1..500</a>
%e 3792 is in the sequence because the concatenation of the prime distinct divisors {2, 3, 79} is 2379, anagram of 3792.
%p with(numtheory):
%p for n from 1 to 140000 do:
%p if type(n,prime)=false
%p then
%p x:=factorset(n):n1:=nops(x): s:=0:s0:=0:
%p for i from n1 by -1 to 1 do:
%p a:=x[i]:b:=length(a):s:=s+a*10^s0:s0:=s0+b:
%p od:
%p if sort(convert(n, base, 10)) = sort(convert(s, base, 10))
%p then
%p printf(`%d, `, n):
%p else
%p fi:fi:
%p od:
%t Select[Range[2,140000],If [!PrimeQ[#],Sort@IntegerDigits@#==Sort[Join@@IntegerDigits[First/@FactorInteger[#]]]]&]
%Y Cf. A023086, A209799.
%Y A121342 is a subsequence.
%K nonn,base
%O 1,1
%A _Michel Lagneau_, Feb 18 2019
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