# File lib/plugins/primes.rb, line 3 def primes(n) return "" if n < 3 table = [] (2 .. n).each do |i| table << i end prime = [] loop do prime << table[0] table = table.delete_if {|x| x % prime.max == 0 } break if table.max < (prime.max ** 2) end r = (table+prime).sort {|a, b| a<=>b } r.join(', ') end