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A098946 Numbers where 3 is the only odd decimal digit.

%I A098946 #13 Apr 18 2020 00:43:04
%S A098946 3,23,30,32,33,34,36,38,43,63,83,203,223,230,232,233,234,236,238,243,
%T A098946 263,283,300,302,303,304,306,308,320,322,323,324,326,328,330,332,333,
%U A098946 334,336,338,340,342,343,344,346,348,360,362,363,364,366,368,380,382
%N A098946 Numbers where 3 is the only odd decimal digit.
%C A098946 This is a regular language in base 10. [_Charles R Greathouse IV_, Oct 05 2011]
%H A098946 Robert Israel, <a href="/A098946/b098946.txt">Table of n, a(n) for n = 1..10000</a>
%H A098946 <a href="/index/Ar#10-automatic">Index entries for 10-automatic sequences</a>
%p A098946 S:= [0,2,3,4,6,8]:
%p A098946 f:= proc(n) local L,i;
%p A098946   L:= convert(n,base,6);
%p A098946   if member(2,L) then
%p A098946     add(S[L[i]+1]*10^(i-1),i=1..nops(L))
%p A098946   fi
%p A098946 end proc:
%p A098946 map(f, [$1..200]); # _Robert Israel_, Feb 05 2019
%t A098946 Select[Range[400],Union[Select[IntegerDigits[#],OddQ]]=={3}&] (* _Harvey P. Dale_, May 05 2017 *)
%o A098946 (Perl) for (0..1000) {
%o A098946     print "$_, " if (/^[023468]*3[023468]*$/)
%o A098946 } # _Charles R Greathouse IV_, Oct 05 2011
%K A098946 base,easy,nonn
%O A098946 1,1
%A A098946 _Eric Angelini_, Oct 21 2004