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Numbers n such that n is divisible by the median of its digits.
1

%I #34 Feb 13 2017 03:37:23

%S 1,2,3,4,5,6,7,8,9,10,11,12,15,18,20,21,22,24,27,30,33,36,40,42,44,45,

%T 48,50,51,54,55,60,63,66,70,72,77,80,81,84,88,90,99,101,102,103,104,

%U 105,106,107,108,109,110,111,112,113,114,115,116,117,118,119

%N Numbers n such that n is divisible by the median of its digits.

%C The first cases that are prime numbers :

%C a(2)=2;

%C a(3)=3;

%C a(5)=5;

%C a(7)=7;

%C a(11)=11;

%C a(44)=101;

%C a(46)=103;

%C a(50)=107.

%C The first difference from A180477 is that n = 100 is in that sequence but not here.

%H Indranil Ghosh, <a href="/A271239/b271239.txt">Table of n, a(n) for n = 1..10000</a>

%e 72 is a member because the median of its digits (7, 2) is 9/2 and 72 is divisible by 9/2 (i.e., the ratio 72/(9/2) is an integer).

%t Select[Range[500], Quiet@ Divisible[#, Median@ IntegerDigits@ #] &] (* _Giovanni Resta_, Apr 08 2016 *)

%Y Cf. A061384, A180477.

%K nonn,base,easy

%O 1,2

%A _José de Jesús Camacho Medina_, Apr 02 2016