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A061831 Multiples of 9 having only even digits.

%I A061831 #18 Aug 07 2021 17:51:16
%S A061831 0,288,468,486,648,666,684,828,846,864,882,2088,2268,2286,2448,2466,
%T A061831 2484,2628,2646,2664,2682,2808,2826,2844,2862,2880,4068,4086,4248,
%U A061831 4266,4284,4428,4446,4464,4482,4608,4626,4644,4662,4680,4806,4824,4842,4860,6048,6066
%N A061831 Multiples of 9 having only even digits.
%H A061831 Robert Israel, <a href="/A061831/b061831.txt">Table of n, a(n) for n = 1..10000</a>
%H A061831 <a href="/index/Ar#10-automatic">Index entries for 10-automatic sequences</a>.
%F A061831 For n >= 2, a(A305826(n)+1) = 2*10^n+88. - _Robert Israel_, Jun 10 2018
%e A061831 648 = 9*72 is a term having all even digits.
%p A061831 f:= proc(k) local L,t;
%p A061831   L:= convert(k,base,5);
%p A061831   t:= 2*add(L[i]*10^(i-1),i=1..nops(L));
%p A061831   if t mod 9 = 0 then t fi
%p A061831 end proc:
%p A061831 map(f, [$0..1000]); # _Robert Israel_, Jun 10 2018
%t A061831 Select[9*Range[0, 700], AllTrue[IntegerDigits[#], EvenQ] &] (* _Harvey P. Dale_, Aug 07 2021 *)
%o A061831 (PARI) is(n)=n%9==0 && #setintersect(Set(digits(n)), [1,3,5,7,9])==0 \\ _Charles R Greathouse IV_, Feb 15 2017
%Y A061831 Cf. A061829, A305826.
%K A061831 nonn,base,easy
%O A061831 1,2
%A A061831 _Amarnath Murthy_, May 29 2001
%E A061831 Corrected and extended by Larry Reeves (larryr(AT)acm.org), May 30 2001
%E A061831 Offset corrected by _Charles R Greathouse IV_, Feb 15 2017
%E A061831 Missing term 2880 inserted by _Robert Israel_, Jun 10 2018