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A309539 Positive numbers that contain both odd and even digits, with no digit repeated.

%I A309539 #16 Jan 09 2025 18:59:41
%S A309539 10,12,14,16,18,21,23,25,27,29,30,32,34,36,38,41,43,45,47,49,50,52,54,
%T A309539 56,58,61,63,65,67,69,70,72,74,76,78,81,83,85,87,89,90,92,94,96,98,
%U A309539 102,103,104,105,106,107,108,109,120,123,124,125,126,127,128,129,130,132,134,136
%N A309539 Positive numbers that contain both odd and even digits, with no digit repeated.
%C A309539 Unlike A318700, where digits can be repeated, this sequence is finite; last term is 9876543210.
%H A309539 Robert Israel, <a href="/A309539/b309539.txt">Table of n, a(n) for n = 1..10000</a>
%e A309539 49 and 50 are in the sequence but 19 and 20 are not.
%p A309539 filter:= proc(n) local L;
%p A309539   L:= convert(n,base,10);
%p A309539   nops(L) = nops(convert(L,set)) and convert(L mod 2,set) = {0,1};
%p A309539 end proc:
%p A309539 select(filter, [$10 .. 1000]); # _Robert Israel_, Jan 09 2025
%t A309539 boeQ[n_]:=Max[DigitCount[n]]==1&&IntegerLength[n]>Count[ IntegerDigits[ n],_?EvenQ]>0; Select[Range[150],boeQ] (* _Harvey P. Dale_, Jul 02 2020 *)
%o A309539 (PARI) isok(n) = my(d=digits(n)); (#d == #Set(d)) && #select(x->(x%2), d) && #select(x->!(x%2), d); \\ _Michel Marcus_, Aug 07 2019
%Y A309539 Cf. A318700, A010784.
%K A309539 nonn,base,fini
%O A309539 1,1
%A A309539 _Enrique Navarrete_, Aug 06 2019