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%I #13 Apr 10 2015 14:14:27
%S 25,26,27,28,34,35,36,38,44,45,46,48,52,54,56,58,62,63,64,65,72,76,82,
%T 84,85,92,99,125,126,128,129,134,135,136,138,143,144,145,146,148,152,
%U 153,154,156,158,162,164,165,172,176,182,183,184,185,192,215,216
%N Composite numbers whose multiplicative persistence is 2.
%C Complement of A046502 with respect to A046511.
%H Harvey P. Dale, <a href="/A199992/b199992.txt">Table of n, a(n) for n = 1..1000</a>
%e 125 -> 1 * 2 * 5-> [ 10 ] -> 1 * 0 -> [ 0 ] -> one digit in two steps.
%t persistence[n_] := Module[{cnt = 0, k = n}, While[k > 9, cnt++; k = Times @@ IntegerDigits[k]]; cnt]; Select[Range[400], ! PrimeQ[#] && persistence[#] == 2 &] (* _T. D. Noe_, Nov 23 2011 *)
%t Select[Range[250],CompositeQ[#]&&Length[NestWhileList[Times@@ IntegerDigits[ #]&,#,#>9&]] == 3&] (* _Harvey P. Dale_, Apr 10 2015 *)
%Y Cf. A046502 (primes whose multiplicative persistence is 2).
%K nonn,base
%O 1,1
%A _Jaroslav Krizek_, Nov 13 2011
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