A045799 - OEIS

%I #14 Sep 08 2019 02:51:47

%S 100,10001,10100,11000,100100,1000011,1001001,1001010,1001100,1010010,

%T 1011000,1100001,1100100,1101000,1110000,10101010,11001100,11011000,

%U 11110000,100000111,100001101,100010101,100010110,100011001,100011100

%N In the list of divisors of n (in binary), each digit 0-1 appears equally often.

%C The corresponding decimal values of the terms are 4, 17, 20, 24, 36, 67, 73, 74, 76, 82, 88, 97, 100, 104, 112, 170, 204, 216, 240, 263, 269, 277, 278, 281, 284, ... - _Amiram Eldar_, Sep 08 2019

%H Amiram Eldar, <a href="/A045799/b045799.txt">Table of n, a(n) for n = 1..10000</a>

%H N. Nomoto, <a href="http://www.geocities.co.jp/Technopolis/1793/09digit.htm">In the list of divisors of n,... </a> [Dead link]

%e E.g. divisors of 10100 are (1, 10, 100, 101, 1010, 10100); the numbers of digits (0-1) are [ 0(9),1(9) ].

%t fQ[v_] := Length[v] == 2 && v[[1]] == v[[2]]; aQ[n_] := fQ[(Tally @ Flatten @ Join @ IntegerDigits[Divisors[n], 2])[[;; , 2]]]; FromDigits /@ IntegerDigits[Select[ Range[284], aQ], 2] (* _Amiram Eldar_, Sep 08 2019 *)

%Y Cf. A038564, A038565, A045810.

%K easy,nonn,base

%O 1,1

%A _Naohiro Nomoto_