My answer to http://challenge.airtime.com/instructions

solver.rb

require 'rubygems'
require 'capybara'
require 'capybara/dsl'

# Yeah Capybara is overkill... YEAH!
Capybara.run_server = false
Capybara.current_driver = :selenium

class Numeric
  def add y
    self + y
  end
  def sub y
    self - y
  end
  def mult y
    self * y
  end
  def div y
    self / y
  end
end

class Solver
  include Capybara::DSL
  def initialize param
    @param = param
    begin
      solve "/#{@param}"
    rescue SyntaxError => se
      find_longest_sequence
    end
  end

  def solve url
    visit url
    answer = eval(find('body').text)
    store answer
    solve "/#{answer}#{@param}"
  end

  def store answer
    @seq ||= [[]]
    active_seq = @seq.last
    if active_seq.empty? or active_seq.last < answer
      active_seq << answer
    else
      @seq << [answer]
    end
  end

  def find_longest_sequence
    longest = []
    for seq in @seq
      if longest.empty? or (seq.length >= longest.length and seq.reduce(:+) > longest.reduce(:+))
        longest = seq
      end
    end
    puts "Sum of longest sequence : #{longest.reduce(:+)}"
  end
end

Capybara.app_host = 'http://challenge.airtime.com'
Solver.new '[email protected]'