There are a bunch of ways of solving this .. you could try just running through the powers of two: 
my$a=256;
for(my$b=1;$b<1E9;$b*=2)
{
  if($a==$b){print'Match!';last;}
}

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In reply to Re: How can I tell if a number is a power of 2? by talexb
in thread How can I tell if a number is a power of 2? by larryk

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