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

%I #7 Feb 15 2017 01:38:08

%S 100,101,110,112,113,114,115,116,117,118,119,121,122,131,133,141,144,

%T 151,155,161,166,171,177,181,188,191,199,200,202,211,212,220,221,223,

%U 224,225,226,227,228,229,232,233,242,244,252,255,262,266,272,277,282,288,292,299,300,303,311,313,322,323,330,331,332,334,335

%N Numbers with an odd number of digits and with an even 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))) = 1.

%F A000035(A043537(a(n))) = 0.

%F a(n) = A210666(n) for n < 244.

%t Select[Range[335], Mod[Length[IntegerDigits[#1]], 2] == 1 && Mod[Length[Union[IntegerDigits[#1]]], 2] == 0 & ]

%Y Cf. A000035, A001633, A043537, A055642, A210666, A280823, A280824, A280826.

%K nonn,base,easy

%O 1,1

%A _Ilya Gutkovskiy_, Jan 08 2017