Problem 34

145 is a curious number, as 1! + 4! + 5! = 1 + 24 + 120 = 145.

Find the sum of all numbers which are equal to the sum of the factorial of their digits.

Note: as 1! = 1 and 2! = 2 are not sums they are not included.

puts (0..50000).select{|i|

    i.to_s.length>1 && i == i.to_s.each_char.map{|d| (1..d.to_i).reduce(1,:*)}.reduce(:+)}.reduce(:+)

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