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A032563 Numbers k such that A102489(k) is divisible by k.

%I A032563 #30 Oct 07 2019 01:13:44
%S A032563 1,2,3,4,5,6,7,8,9,1038,1040,2078,2080,2118,2120,3158,3160,3200,4198,
%T A032563 4238,4240,5278,5280,5318,5320,6358,6360,6400,7398,7438,7440,8478,
%U A032563 8480,8518,8520,9558,9560,9600,12480,25440,38400,112308,449440
%N A032563 Numbers k such that A102489(k) is divisible by k.
%H A032563 Robert Israel, <a href="/A032563/b032563.txt">Table of n, a(n) for n = 1..71</a>
%e A032563 9_10 / 9_16 = 9/9 = 1;
%e A032563 4152_10 / 1038_16 = 4152/1038 = 4;
%e A032563 4160_10 / 1040_16 = 4160/1040 = 4;
%e A032563 8312_10 / 2078_16 = 8312/2078 = 4.
%p A032563 d:= Vector(10^7,1):
%p A032563 for i from 1 to 7 do
%p A032563    inds:= 10^i*[$1..10^(7-i)];
%p A032563    d[inds]:= (2*16^i+3)/5;
%p A032563 od:
%p A032563 b:= Vector(10^7):
%p A032563 b[1]:= 1:
%p A032563 for i from 2 to 10^7 do
%p A032563   b[i]:= b[i-1]+d[i]
%p A032563 od:
%p A032563 select(t-> (b[t]/ t)::integer, [$1..10^7]); # _Robert Israel_, Aug 30 2015
%t A032563 Select[Range[16^5], IntegerQ[FromDigits[IntegerDigits[#], 16]/#] &] (* _Michael De Vlieger_, Aug 29 2015 *)
%Y A032563 Cf. A032564, A102489.
%K A032563 nonn,base
%O A032563 1,2
%A A032563 _Patrick De Geest_, Apr 15 1998