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%I #20 Jan 31 2013 03:18:04
%S 22,121,202,1111,2222,10201,12221,20222,22121,111221,112211,202222,
%T 220121,221111,222211,1021211,1112221,1122011,1222201,2021111,2022002,
%U 2022121,2121101,2122111,2200202,2202211,2211121,2212111,2222011,10212211,11112211,11121011
%N Composite numbers n such that largest digit of all divisors of n is 2.
%C Also composite numbers n such that largest digit of concatenation of all divisors (A037278) of n is 2.
%C Composite numbers n such that A209928(n) = 2.
%C Complement of A106100 with respect to A221697.
%e Number 10201 is in the sequence because the largest digit of all divisors of 10201 (1, 101, 10201) is 2.
%t t = {}; n = 1; While[Length[t] < 40, n++; m = FromDigits[IntegerDigits[n, 3]]; If[! PrimeQ[m] && Max[Union[Flatten[IntegerDigits[Divisors[m]]]]] <= 2, AppendTo[t, m]]]; t (* _T. D. Noe_, Jan 30 2013 *)
%Y Cf. A209928 (largest digit of all divisors of n), A221697.
%K nonn,base
%O 1,1
%A _Jaroslav Krizek_, Jan 22 2013
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