Ads
related to: tests for divisibility of numberskutasoftware.com has been visited by 10K+ users in the past month
Search results
Results from the WOW.Com Content Network
To test the divisibility of a number by a power of 2 or a power of 5 (2 n or 5 n, in which n is a positive integer), one only need to look at the last n digits of that number. To test divisibility by any number expressed as the product of prime factors , we can separately test for divisibility by each prime to its appropriate power.
Given an integer n (n refers to "the integer to be factored"), the trial division consists of systematically testing whether n is divisible by any smaller number. Clearly, it is only worthwhile to test candidate factors less than n, and in order from two upwards because an arbitrary n is more likely to be divisible by two than by three, and so on.
The method is along the same lines as the divisibility rule for 11 using the property 10 ≡ -1 (mod 11). The two properties of 1001 are 1001 = 7 × 11 × 13 in prime factors 10 3 ≡ -1 (mod 1001) The method simultaneously tests for divisibility by any of the factors of 1001. First, the digits of the number being tested are grouped in blocks ...
The first deterministic primality test significantly faster than the naive methods was the cyclotomy test; its runtime can be proven to be O((log n) c log log log n), where n is the number to test for primality and c is a constant independent of n. Many further improvements were made, but none could be proven to have polynomial running time.
1 Divisibility. 2 Fractions. 3 Modular arithmetic. 4 Arithmetic functions. ... Lucas–Lehmer test for Mersenne numbers; AKS primality test; Integer factorization
The equivalent of the usual test for divisibility for 3 is that if you take the units digit of your number, add 3 times the tens digit, add 2 times the hundreds digit, subtract the thousands digit, subtract three times the tenthousands digit, subtract 2 times the hundredthousands digit, add the millions digit, and so on (repeating the pattern 1 ...
Using fast algorithms for modular exponentiation and multiprecision multiplication, the running time of this algorithm is O(k log 2 n log log n) = Õ(k log 2 n), where k is the number of times we test a random a, and n is the value we want to test for primality; see Miller–Rabin primality test for details.
The multiples of a given prime are generated as a sequence of numbers starting from that prime, with constant difference between them that is equal to that prime. [1] This is the sieve's key distinction from using trial division to sequentially test each candidate number for divisibility by each prime. [2]
Ads
related to: tests for divisibility of numberskutasoftware.com has been visited by 10K+ users in the past month