%I #10 May 30 2015 08:35:23
%S 6,16,28,32,44,48,68,74,82,84,86,116,123,128,132,144,147,148,161,168,
%T 174,182,184,186,213,218,224,228,231,238,242,244,246,264,267,272,276,
%U 282,288,289,298,312,321,328,344,368,374,377,378,382,386,387,414,417,418,422
%N Composite numbers whose multiplicative digital root is 6.
%C Complement of A201019 with respect to A034053.
%H Harvey P. Dale, <a href="/A201020/b201020.txt">Table of n, a(n) for n = 1..1000</a>
%e Number 128 is in sequence because 1*2*8=16, 1*6=6.
%t mdr6Q[n_]:=CompositeQ[n]&&NestWhile[Times@@IntegerDigits[#]&,n,#>9&] ==6; Select[Range[500],mdr6Q] (* _Harvey P. Dale_, May 30 2015 *)
%Y Cf. A201019 (primes whose multiplicative digital root is 6), A034053 (numbers whose multiplicative digital root is 6).
%K nonn,base
%O 1,1
%A _Jaroslav Krizek_, Nov 25 2011
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