%I #9 Aug 27 2012 11:06:27
%S 9,33,91,119,133,1119,1133,1191,1313,1331,1911,3113,3131,3311,9111,
%T 11133,11191,11313,11331,11911,13113,13131,13311,19111,31113,31131,
%U 31311,33111,91111,111133,111313,111331,111911,113113,113311,119111,131131,133111,191111,311113
%N Composite numbers whose multiplicative digital root is 9.
%C Also composite numbers whose product of digits is 9. Complement of A107695 with respect to A034056.
%e Number 133 is in sequence because 1*3*3=9.
%t Select[Range[320000],!PrimeQ[#]&&Times@@IntegerDigits[#]==9&] (* _Harvey P. Dale_, Aug 27 2012 *)
%Y Cf. A107695 (primes whose multiplicative digital root is 9), A034056 (numbers whose multiplicative digital root is 9).
%K nonn,base
%O 1,1
%A _Jaroslav Krizek_, Nov 25 2011
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