A Blum integer is a semiprime—that is, the product of two distinct primes—whose factors have the form 4k+3 for some integer k. The number 21 is a Blum integer because its two prime factors, 3 and 7, have the form 4k+3 with k = 0 and k = 1. The number 123 is a semiprime because it is 3x41, but it is not a Blum integer because 41 is not 3 more than a multiple of 4. The number 1463 is not a Blum integer: although its prime factors are distinct and each 3 more than a multiple of 4, there are three of them, not two.
Write a function to determine whether the numbers in a matrix are Blum integers.
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