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%I #12 Sep 08 2022 08:46:17
%S 0,2,4,6,8,9,20,22,24,26,28,29,40,42,44,46,48,49,60,62,64,66,68,69,80,
%T 82,84,86,88,89,90,92,94,96,98,99,200,202,204,206,208,209,220,222,224,
%U 226,228,229,240,242,244,246,248,249,260,262,264,266
%N Numbers without the decimal digits 1, 3, 5 and 7.
%H Robert Israel, <a href="/A276138/b276138.txt">Table of n, a(n) for n = 1..10000</a>
%F a(6n-6+k) = 10 a(n) + a(k) for k = 1..6. - _Robert Israel_, Aug 24 2016
%p S:= [0]:
%p for d from 1 to 4 do S:= map(t -> seq(10*t+i,i=[0,2,4,6,8,9]), S) od:
%p S; # _Robert Israel_, Aug 24 2016
%t Select[Select[Select[Select[Range[0, 400], FreeQ[IntegerDigits@#, 1] &], FreeQ[IntegerDigits@#, 3] &], FreeQ[IntegerDigits@#, 5] &], FreeQ[IntegerDigits@#, 7] &]
%o (Magma) [n: n in [0..500] | IsEmpty(Set([1,3,5,7]) meet Set(Intseq(n)))];
%Y Cf. A168501, A276137.
%K nonn,base,easy
%O 1,2
%A _Vincenzo Librandi_, Aug 22 2016