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Hi,
I noticed something interesting while playing around with twin primes (pairs of primes that differ by 2). Here is what I noticed:
Conjecture: The product of twin primes—excluding the pair (3, 5)—always has a digital root of 8.
Just to clarify, the digital root of a number is the single-digit value you get by repeatedly summing its digits until only one digit remains. For example, the digital root of 77 is 7 + 7 = 14, and then 1 + 4 = 5.
I tested this on several examples, and it seems to hold, but I’m not sure if it’s a well-known result or something that breaks down for larger primes.
Is this an obvious consequence of some known number theory property? Would love to hear your thoughts!
I noticed something interesting while playing around with twin primes (pairs of primes that differ by 2). Here is what I noticed:
Conjecture: The product of twin primes—excluding the pair (3, 5)—always has a digital root of 8.
Just to clarify, the digital root of a number is the single-digit value you get by repeatedly summing its digits until only one digit remains. For example, the digital root of 77 is 7 + 7 = 14, and then 1 + 4 = 5.
I tested this on several examples, and it seems to hold, but I’m not sure if it’s a well-known result or something that breaks down for larger primes.
Is this an obvious consequence of some known number theory property? Would love to hear your thoughts!