16 lines
421 B
Clojure
16 lines
421 B
Clojure
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(def primes
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"Lazy sequence of all the prime numbers."
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(concat
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[2 3 5 7]
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(lazy-seq
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(let [primes-from
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(fn primes-from [n [f & r]]
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(if (some #(zero? (rem n %))
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(take-while #(<= (* % %) n) primes))
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(recur (+ n f) r)
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(lazy-seq (cons n (primes-from (+ n f) r)))))
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wheel (cycle [2 4 2 4 6 2 6 4 2 4 6 6 2 6 4 2
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6 4 6 8 4 2 4 2 4 8 6 4 6 2 4 6
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2 6 6 4 2 4 6 2 6 4 2 4 2 10 2 10])]
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(primes-from 11 wheel)))))
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