2019-02-16, 18:10 | #1 |
Feb 2019
10000_{2} Posts |
Primality based on digital root
Hi!
Has anyone besides me noticed this? Primes are the sum of two CONSECUTIVE integers ONLY as follows: Prime DR1 = integer DR0 + integer DR1 Prime DR2 = integer DR5 + integer DR6 Prime DR4 = integer DR6 + integer DR7 Prime DR5 = integer DR2 + integer DR3 Prime DR7 = integer DR3 + integer DR4 Prime DR8 = integer DR8 + integer DR0 |
2019-02-16, 20:01 | #2 |
"Serge"
Mar 2008
Phi(4,2^7658614+1)/2
2^{3}·5·229 Posts |
Yeah. And it has nothing to do with "primes". Primes in your message is a red herring.
This is called modular arithmetic. Look it up. DR is nothing else than mod(9). What you are doing is: using mod(9) you are trying to solve: x + (x+1) = a (mod 9). But the solution is obvious: x = (a-1)/2 (mod 9) Example: you are saying: "DR4 = integer DR6 + integer DR7". Or in other words: "4 = 6+7 (mod 9)". That's obvious, because 6 = (4-1)/2 (mod 9). (look up how to divide by 2 in a modular system) |
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