Prints out a multiplication table. Written in Ruby for brevity. .NET equivalents in comments.

mult-table.rb

## To execute, install Ruby, download file, and run:
#  ruby mult-table.rb

THREE_SPACES = ' ' * 3                                        # new String(' ', 3)

def print_header(rows)
  print THREE_SPACES                                          # Console.Write(...)
  1.upto(rows) { |number| print "#{THREE_SPACES} #{number}" } # String.Format(...)
  puts                                                        # Console.WriteLine(...)
end

def print_rows(rows)
  1.upto(rows) do |row|                                       # Enumerable.Range(...)
    print "#{THREE_SPACES} #{row}"
    1.upto(rows) { |number| print "#{THREE_SPACES} #{row * number}" }
    puts
  end
end

def print_table(rows)
  print_header(rows)
  print_rows(rows)
end

print_table(3) ## =>        1    2    3
               #          1    1    2    3
               #          2    2    4    6
               #          3    3    6    9