permutation.rb

def three_amigos_please
  0.upto(128) do |i|
    0.upto(128) do |j|
      0.upto(128) do |k|
        if i != j and j != k and i != k
          yield ("0"*128).split('').map {|n| [i,j,k].include?(n) ? "1" : "0"  }.join('')
        end
      end
    end
  end
end

alias permutation three_amigos_please