Primes Flashcards
not prime
composite
prove there are infinitely many primes
Q = p1p2…pn + 1
Mersenne Prime
2^p - 1
The prime number theorem
lim as x-> infinity pi(x)/(x/ln(x)) = 1
What does the prime number theorem say about the odds of a number being prime
1/ln(n)
All primes greater than 2 are;
odd
For every positive integer n there is an arithmetic progression of length n consisting of
entirely primes
two integers m and n are relatively prime if
gcd(m,n) = 1
gcd(a,b) * lcm(a,b) =
a*b
The multiplicative inverse of n mod(m) exists iff
m and n are relatively prime
You should check out a proof of the uniqueness of the prime facorization of a positive integer
do it
The chinese remainder theorem
if
x = i mod m
x = j mod n
x = k mod o
and m n o are pairwise relatively prime
then
x = inn’oo’ + jmm’oo’ + kmm’oo’
Fermat’s little theorem
if p is prime and a is not divisible by p then
a^(p-1) = 1 mod p
what is 7^222 mod 11
5
when is m pseudoprime mod n
m^(n-1) = 1 (mod n)