A positive integer pair , is called an "almost twin prime pair", if one of the pair is a prime and the other is either a prime or a semiprime. A semiprime is a natural number that is a product of only two and exactly two (not necessarily distinct) prime numbers (e.g. 4, 6, 9, , , , , , ...).
Listed below are all almost twin prime pairs with no element greater than :
Our task in this exercise is, to create a function that counts the number of almost twin prime pairs whose elements are less than or equal to a given limit Therefore for , our function should return .
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Last Solution submitted on Mar 21, 2026

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William George Berken David Hill GeeTwo

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