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%I #11 Mar 21 2015 04:54:18
%S 1,2,4,8,9,16,32,64,81,128,256,512,625,729,1024,2048,4096,6561,7776,
%T 8192,16384,32768,59049,65536,117649,131072,262144,390625,524288,
%U 531441,1048576,2097152,4194304,4782969,8388608,16777216,33554432,43046721
%N Numbers of the form (m/n)^(m-n) with m >=n.
%C All powers of 2 are present, even powers of 3, fourth powers of 5, etc. - _Robert G. Wilson v_
%e The 10th element is a=128 with m = 14 and n =7 because 128 =(14/7)^(14-7).
%p a:=proc(N) local a, m,n; for m from 1 to N do for n from 1 to m do a:=(m/n)^(m-n); if(floor(a)=a) then print(a) fi; od; od; end: # convert into set # sort set
%t Take[ Select[ Union[ Flatten[ Table[(m/n)^(m - n), {m, 52}, {n, m}]]], IntegerQ[ # ] &], 40] (* _Robert G. Wilson v_ *)
%K nonn
%O 1,2
%A _Paolo P. Lava_ and _Giorgio Balzarotti_, Nov 12 2005
%E Corrected and extended by _Robert G. Wilson v_, Nov 14 2005
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