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Numbers k that divide 2^k + 8.
8

%I #31 Sep 13 2022 09:16:46

%S 1,2,4,5,6,8,12,18,24,36,72,88,198,228,1032,2412,2838,4553,5958,10008,

%T 24588,25938,46777,65538,75468,82505,130056,143916,200364,540738,

%U 598818,750852,797478,923628,958212,1151538,1250568,1505388,1647396,2365128,2964036,3490028,3704418,3844808

%N Numbers k that divide 2^k + 8.

%H Chai Wah Wu, <a href="/A245319/b245319.txt">Table of n, a(n) for n = 1..929</a> (terms 1..58 from Harvey P. Dale)

%H OEIS Wiki, <a href="/wiki/2^n mod n">2^n mod n</a>

%e 2^4 + 8 = 24 is divisible by 4. Thus 4 is a term of this sequence.

%e 2^5 + 8 = 40 is divisible by 5. Thus 5 is a term of this sequence.

%p select(n -> 2 &^ n + 8 mod n = 0, [$1..10^6]); # _Robert Israel_, Jul 18 2014

%t Join[Select[Range[7],Divisible[2^#+8,#]&],Select[Range[4000000], Abs[ PowerMod[ 2,#,#]-#]==8&]] (* _Harvey P. Dale_, May 25 2016 *)

%o (PARI) for(n=1,10^9,if(Mod(2,n)^n==Mod(-8,n),print1(n,", ")));

%Y The odd terms form A357125.

%Y Cf. A015922.

%K nonn

%O 1,2

%A _Derek Orr_, Jul 17 2014