Not declaring a new variable speeds it up by a reasonable amount - and dropping the unneeded printf:

for( 0b000000000000111111..0b111111000000000000 ) {
  $_ = sprintf("%018b",$_);
  next unless /^0*10*10*10*10*10*10*$/;
  print "$_\n";
}
[download]

cLive ;-)

--
seek(JOB,$$LA,0);