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Numbers with an even number of digits and with an odd number of distinct digits.
3

%I #9 Mar 31 2019 15:07:09

%S 11,22,33,44,55,66,77,88,99,1002,1003,1004,1005,1006,1007,1008,1009,

%T 1012,1013,1014,1015,1016,1017,1018,1019,1020,1021,1022,1030,1031,

%U 1033,1040,1041,1044,1050,1051,1055,1060,1061,1066,1070,1071,1077,1080,1081,1088,1090,1091,1099,1102,1103,1104,1105,1106,1107,1108,1109

%N Numbers with an even number of digits and with an odd number of distinct digits.

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/Digit.html">Digit</a>

%H <a href="/index/Ar#10-automatic">Index entries for 10-automatic sequences</a>.

%F A000035(A055642(a(n))) = 0.

%F A000035(A043537(a(n))) = 1.

%t Select[Range[1110], Mod[Length[IntegerDigits[#1]], 2] == 0 && Mod[Length[Union[IntegerDigits[#1]]], 2] == 1 & ]

%t endQ[n_]:=Module[{idn=IntegerDigits[n]},EvenQ[Length[idn]]&&OddQ[ Length[ Union[ idn]]]]; Select[Range[1200],endQ] (* _Harvey P. Dale_, Mar 31 2019 *)

%Y Cf. A000035, A001637, A043537, A055642, A280823, A280824, A280825.

%K nonn,base,easy

%O 1,1

%A _Ilya Gutkovskiy_, Jan 08 2017