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Numbers n such that floor(reverse(n)/n) = 2.
2

%I #9 Feb 05 2019 13:49:36

%S 13,14,25,26,27,28,38,39,103,113,123,133,143,153,154,163,164,173,174,

%T 183,184,193,194,205,206,215,216,225,226,235,236,245,246,255,256,257,

%U 265,266,267,275,276,277,285,286,287,295,296,297,298,307,308,309,317

%N Numbers n such that floor(reverse(n)/n) = 2.

%H Edward Jiang, <a href="/A079831/b079831.txt">Table of n, a(n) for n = 1..10000</a>

%e 14 is a member as floor(41/14) = 2.

%t Select[Range[400],Floor[IntegerReverse[#]/#]==2&] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Feb 05 2019 *)

%o (ARIBAS) for n := 1 to 318 do nst := ""; st := itoa(n); for i := 0 to length(st) - 1 do nst := concat(st[i],nst); end; a := atoi(nst); if a div n = 2 then write(n,",") end; end;

%o (PARI) for(n=1, 1100, if(floor(eval(concat(Vecrev(Str(n))))/n)==2, print1(n, ", "))) \\ _Edward Jiang_, Aug 19 2014

%o (Python)

%o from math import floor

%o for i in range(1,1000):

%o ....if floor(int(str(i)[::-1])/i)==2:

%o ........print(i)

%o # _Edward Jiang_, Aug 19 2014

%Y Cf. A079832.

%K base,nonn

%O 1,1

%A _Amarnath Murthy_, Feb 11 2003

%E Edited and extended by _Klaus Brockhaus_, Feb 12 2003