24/7 Pet Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Perfect number - Wikipedia

    en.wikipedia.org/wiki/Perfect_number

    Perfect number. In number theory, a perfect number is a positive integer that is equal to the sum of its positive proper divisors, that is, divisors excluding the number itself. For instance, 6 has proper divisors 1, 2 and 3, and 1 + 2 + 3 = 6, so 6 is a perfect number. The next perfect number is 28, since 1 + 2 + 4 + 7 + 14 = 28.

  3. 7 - Wikipedia

    en.wikipedia.org/wiki/7

    On the other hand, 7 is the number of partitions of 5, a value n which yields the third perfect number 496 for 2 n − 1 (2 n − 1), by the Euclid-Euler theorem. 7 is the only number D for which the equation 2 n − D = x 2 has more than two solutions for n and x natural. In particular, the equation 2 n − 7 = x 2 is known as the Ramanujan ...

  4. List of Mersenne primes and perfect numbers - Wikipedia

    en.wikipedia.org/wiki/List_of_Mersenne_primes...

    Mersenne primes and perfect numbers are two deeply interlinked types of natural numbers in number theory. Mersenne primes, named after the friar Marin Mersenne, are prime numbers that can be expressed as 2p − 1 for some positive integer p. For example, 3 is a Mersenne prime as it is a prime number and is expressible as 22 − 1.

  5. Euclid–Euler theorem - Wikipedia

    en.wikipedia.org/wiki/Euclid–Euler_theorem

    The Euclid–Euler theorem states that an even natural number is perfect if and only if it has the form 2 p−1 M p, where M p is a Mersenne prime. The perfect number 6 comes from p = 2 in this way, as 2 2−1 M 2 = 2 × 3 = 6, and the Mersenne prime 7 corresponds in the same way to the perfect number 28.

  6. Square number - Wikipedia

    en.wikipedia.org/wiki/Square_number

    In mathematics, a square number or perfect square is an integer that is the square of an integer; [1] in other words, it is the product of some integer with itself. For example, 9 is a square number, since it equals 32 and can be written as 3 × 3 . The usual notation for the square of a number n is not the product n × n, but the equivalent ...

  7. Golden ratio - Wikipedia

    en.wikipedia.org/wiki/Golden_ratio

    The golden ratio's negative −φ and reciprocal φ−1 are the two roots of the quadratic polynomial x2 + x − 1. The golden ratio is also an algebraic number and even an algebraic integer. It has minimal polynomial. This quadratic polynomial has two roots, and. The golden ratio is also closely related to the polynomial.

  8. If You Have Life Path Number 7, Here's Exactly What ... - AOL

    www.aol.com/lifestyle/life-path-number-7-heres...

    So, in this case, your life path number is 7. The only time you would NOT reduce the final number is if you get 11 or 22 or 33. Those are considered master numbers, and they hold a special meaning ...

  9. Euclid's theorem - Wikipedia

    en.wikipedia.org/wiki/Euclid's_theorem

    Every positive integer has a unique factorization into a square-free number r and a square number s 2. For example, 75,600 = 2 4 3 3 5 2 7 1 = 21 ⋅ 60 2. Let N be a positive integer, and let k be the number of primes less than or equal to N. Call those primes p 1, ... , p k. Any positive integer a which is less than or equal to N can then be ...