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%I #6 Oct 01 2013 21:35:30
%S 22,26,33,34,38,39,44,46,51,52,55,57,58,62,65,66,68,69,74,76,77,78,82,
%T 85,86,87,88,91,92,93,94,95,99,102,104,106,110,111,114,115,116,117,
%U 118,119,122,123,124,129,130,132,133,134,136,138,141,142,145,146,148,152
%N Numbers with at least 2 different numbers of digits among their prime factors.
%C Complement of A162421. There are no prime numbers in this sequence.
%C These numbers can also be called factor rough numbers.
%C Basically, the number of digits of A020639(k) and of A006530(k) must differ to admit k into the sequence.
%F {k >1: A055642(A020639(k)) <> A055642(A006530(k)) }. - R. J. Mathar, Sep 16 2009
%e 1111 = 11*101 has factors with different digital lengths. Also it is the first occurrence that differs from A084891.
%o (PARI) factorrough(m,n) =
%o {
%o local(x,a,j,f,ln);
%o for(x=m,n, f=0; a = ifactor(x); for(j=2,length(a), ln=length(Str(a[j-1])); if(length(Str(a[j]))!=ln,f=1;break);); if(f,print1(x",")););
%o }
%Y Cf. A084891, A162457
%K base,nonn
%O 1,1
%A _Cino Hilliard_, Jul 03 2009
%E Offset set to 1, definition shortened - _R. J. Mathar_, Sep 16 2009
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