16 lines
308 B
Text
16 lines
308 B
Text
func twin_primes_count(upto) {
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var count = 0
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var p1 = 2
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each_prime(3, upto, {|p2|
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if (p2 - p1 == 2) {
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++count
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}
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p1 = p2
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})
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return count
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}
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for n in (1..9) {
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var count = twin_primes_count(10**n)
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say "There are #{count} twin primes <= 10^#{n}"
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}
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