Data commit

Task/Farey-sequence/Ruby/farey-sequence.rb

@@ -0,0 +1,16 @@
+def farey(n, length=false)
+  if length
+    (n*(n+3))/2 - (2..n).sum{|k| farey(n/k, true)}
+  else
+    (1..n).each_with_object([]){|k,a|(0..k).each{|m|a << Rational(m,k)}}.uniq.sort
+  end
+end
+
+puts 'Farey sequence for order 1 through 11 (inclusive):'
+for n in 1..11
+  puts "F(#{n}): " + farey(n).join(", ")
+end
+puts 'Number of fractions in the Farey sequence:'
+for i in (100..1000).step(100)
+  puts "F(%4d) =%7d" % [i, farey(i, true)]
+end