When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Table of divisors - Wikipedia

    en.wikipedia.org/wiki/Table_of_divisors

    Print/export Download as PDF ... For example, 3 is a divisor of 21, since 21/7 = 3 (and therefore 7 is also a divisor of 21). ... 8: 1, 2, 4, 8 4 15 7 deficient ...

  3. Deficient number - Wikipedia

    en.wikipedia.org/wiki/Deficient_number

    In number theory, a deficient number or defective number is a positive integer n for which the sum of divisors of n is less than 2n. Equivalently, it is a number for which the sum of proper divisors (or aliquot sum) is less than n. For example, the proper divisors of 8 are 1, 2, and 4, and their sum is less than 8, so 8 is deficient.

  4. Table of Gaussian integer factorizations - Wikipedia

    en.wikipedia.org/wiki/Table_of_Gaussian_Integer...

    The entry 4+2i = −i(1+i) 2 (2+i), for example, could also be written as 4+2i= (1+i) 2 (1−2i). The entries in the table resolve this ambiguity by the following convention: the factors are primes in the right complex half plane with absolute value of the real part larger than or equal to the absolute value of the imaginary part.

  5. Aliquot sum - Wikipedia

    en.wikipedia.org/wiki/Aliquot_sum

    In number theory, the aliquot sum s(n) of a positive integer n is the sum of all proper divisors of n, that is, all divisors of n other than n itself. That is, = |,. It can be used to characterize the prime numbers, perfect numbers, sociable numbers, deficient numbers, abundant numbers, and untouchable numbers, and to define the aliquot sequence of a number.

  6. Highly abundant number - Wikipedia

    en.wikipedia.org/wiki/Highly_abundant_number

    In number theory, a highly abundant number is a natural number with the property that the sum of its divisors (including itself) is greater than the sum of the divisors of any smaller natural number. Highly abundant numbers and several similar classes of numbers were first introduced by Pillai ( 1943 ), and early work on the subject was done by ...

  7. 15 (number) - Wikipedia

    en.wikipedia.org/wiki/15_(number)

    M = 15 The 15 perfect matchings of K 6 15 as the difference of two positive squares (in orange).. 15 is: The eighth composite number and the sixth semiprime and the first odd and fourth discrete semiprime; [1] its proper divisors are 1, 3, and 5, so the first of the form (3.q), [2] where q is a higher prime.

  8. Greatest common divisor - Wikipedia

    en.wikipedia.org/wiki/Greatest_common_divisor

    The elements 2 and 1 + √ −3 are two maximal common divisors (that is, any common divisor which is a multiple of 2 is associated to 2, the same holds for 1 + √ −3, but they are not associated, so there is no greatest common divisor of a and b.

  9. Zsigmondy's theorem - Wikipedia

    en.wikipedia.org/wiki/Zsigmondy's_theorem

    In number theory, Zsigmondy's theorem, named after Karl Zsigmondy, states that if > > are coprime integers, then for any integer , there is a prime number p (called a primitive prime divisor) that divides and does not divide for any positive integer <, with the following exceptions: