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%I #9 Mar 14 2015 17:58:01
%S 1,3,4,5,6,8,9,10,11,12,14,16,17,18,20,24,32,33,34,36,37,40,42,48,52,
%T 64,65,66,67,68,70,72,76,80,88,96,112,128,129,130,132,135,136,142,144,
%U 156,160,184,192,240,256,257,258,260,264,272,288,320,352,384,448,512,513
%N Positive integers that can be expressed in the form (a*2^a)/(b*2^b) where a and b are positive integers.
%C Odd values > 1 are of the form 2^n + odd divisor of n.
%e 6 is included because 6 = (6*2^6)/(4*2^4)
%e 12 is a member because 12 = (3*2^3)/(1*2^1) = (9*2^9)/(6*2^6). Entries which are generated in two or more different ways are 1,12,20,32,48,72,80,112,160,192,256,576,768,..., . - _Robert G. Wilson v_, May 10 2006
%t lst = {1}; Do[ If[ (Log[10, a] + a*Log[10, 2]) - (Log[10, b] + b*Log[10, 2]) < 3 && IntegerQ[(a*2^a)/(b*2^b)], AppendTo[lst, (a*2^a)/(b*2^b)]; Print[(a*2^a)/(b*2^b)]], {a, 4620}, {b, Max[1, a - 9(* =Log[2, 10^3] *)], a-1}]; lst (* _Robert G. Wilson v_, May 10 2006 *)
%K nonn
%O 1,2
%A Sam Handler (sam_5_5_5_0(AT)yahoo.com), Oct 09 2005
%E More terms from _David W. Wilson_
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