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require 'prime'
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deceptives = Enumerator.new do |y|
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10.step(by: 10) do |n|
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[1,3,7,9].each do |digit|
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cand = n + digit
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next if cand % 3 == 0 || cand.prime?
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repunit = ("1"*(cand-1)).to_i
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y << cand if (repunit % cand) == 0
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end
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end
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end
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p deceptives.take(25).to_a
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