Tags » Primes

A Different Kind of Prime

I was recently blessed to spend a girls weekend with my adult daughter. While driving to brunch we were talking about our fitness levels and I remarked that mine had changed dramatically over the last 15 years. 315 more words


Numbers as products of primes (a useful calculation practice). And the general beauty of primes.

Simon spent hours calculating – something he’s not particularly fond of if it were simple/ pointless sums, the way schoolkids work. His was not pointless!  He did it with the solemn purpose of expressing natural numbers as products of primes, the atoms of all numbers. 38 more words


Doing Mod N Via Mod R

Variations on Montgomery’s trick

Peter Montgomery is a cryptographer at Microsoft. Just recently, Joppe Bos and Arjen Lenstra have edited a book titled Topics in Computational Number Theory Inspired by Peter L. 1,314 more words


Primes & Factors II

Assignment’s Requirements

def output_prime_factors(x):
    x = round(x)
    x = int(x)
    i = 0
    while i= 2:
        if a==x:
            for y in range(2,a):
                if not ( a % y ):
                    return False
	    return False
        return True
        return False

def get_nth_prime(x):
    count = 0
    num = 0
    if type(x) == (float):
        return None
    while count != x:
        if is_prime(num):
            count = count + 1
        num = num + 1
    if count == float:
        return None
    if count == x:
        return num - 1
if __name__ == '__main__':
    print get_nth_prime(4)

Sums of Small Divisors


The following problem originates (as far as I can tell) with Douglas Iannucci and was relayed to me via Brian Freidin… 1,243 more words

Number Theory

Prime Number Problem

Following is a problem about prime factorization of the sum of consecutive odd primes. (source: problem 80 from The Green Book of Mathematical Problems) 211 more words

Problem Solving

Fast and slow machines

In my previous post, I presented three hypothetical machines which take a positive integer as input and give us something else as output:

  1. a…
  2. 1,030 more words
Number Theory