Compact and simple Ruby implementations of a handful of random entries from the "The On-Line Encyclopedia of Integer Sequences®"
Really just a sportive exercise in Ruby coding. They may be helpful for others to learn about include Enumerable or a starting point for you to implement your own favorite sequence.
irb(main):001:0> require'oeis'=>trueirb(main):002:0> OEIS.sequences.count=>10irb(main):003:0> OEIS.sequences.sample=>OEIS::A006928irb(main):004:0> OEIS::A003418.first(10)=>[1,2,6,12,60,60,420,840,2520,2520]irb(main):005:0> seq=OEIS::A003418.new=>#<OEIS::A003418:0x312b34e3 @counter=0, @factors={}, @step=#<Proc:0x26844abb@oeis.rb:58 (lambda)>>irb(main):006:0> seq.take(10)=>[1,2,6,12,60,60,420,840,2520,2520]irb(main):007:0> seq.take(10)=>[27720,27720,360360,360360,360360,720720,12252240,12252240,232792560,232792560]irb(main):008:0> seq.take(10)=>[232792560,232792560,5354228880,5354228880,26771144400,26771144400,80313433200,80313433200,2329089562800,2329089562800]irb(main):009:0> OEIS::A006928.first(10000).map{|i|i-1.5}.inject(&:+)=>4.0irb(main):010:0> OEIS::A006928.first(1000000).map{|i|i-1.5}.inject(&:+)=>14.0