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A023075 Positive numbers k such that k and 4*k are anagrams in base 8 (written in base 8).

%I A023075 #13 Aug 07 2025 03:04:53
%S A023075 1024,1042,1463,10024,10042,10204,10240,10346,10402,10420,10634,12245,
%T A023075 12425,14063,14306,14367,14603,14630,14637,14763,16347,16743,17024,
%U A023075 17042,17463,100024,100042,100204,100240,100346,100402,100420,100634,102004
%N A023075 Positive numbers k such that k and 4*k are anagrams in base 8 (written in base 8).
%H A023075 Robert Israel, <a href="/A023075/b023075.txt">Table of n, a(n) for n = 1..10000</a>
%p A023075 filter:= proc(n)
%p A023075   sort(convert(n,base,8))=sort(convert(4*n,base,8))
%p A023075 end proc:
%p A023075 g:= proc(n) local L; L:= convert(n,base,8);
%p A023075 add(L[i]*10^(i-1),i=1..nops(L))
%p A023075 end proc:
%p A023075 map(g, select(filter, [seq(seq(i,i=8^j .. 2*8^j-1),j=1..5)])); # _Robert Israel_, Dec 25 2019
%t A023075 FromDigits[IntegerDigits[#, 8]] & /@ Select[Range[50000], SameQ @@ Sort /@ IntegerDigits[{#, 4*#}, 8] &] (* _Amiram Eldar_, Aug 07 2025 *)
%Y A023075 Cf. A007094.
%K A023075 nonn,base
%O A023075 1,1
%A A023075 _David W. Wilson_