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Tessmore / gr_v4

Software engineering group V4 repository
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Week 6: if you have read this and you have no questions, please close this issue. #2

Open BertLisser opened 11 years ago

BertLisser commented 11 years ago 
Assignment 4.
Time spent: 1 hour
Use the list of composite numbers to test Fermat's primality check. What is the
least composite number that you can find that fools the check, for `testF k` with
k = 1; 2; 3 ? What happens if you increase k?

Answer: If you keep running this test, eventually even the first number will slip through,
so 4 is the smallest composite number that is able to slip through the test.
The larger you make K, the smaller the chance that some number will fall through (as more checks are done),
hence the returned number is larger.

You must illustrate this with data.

 Report on your findings:
*** Exception: 95513421886551384655206308507......7518292017809047571302187007 is not a prime.
*** Exception: 13454128316990507273441234211......1764350982066467259298086911 is not a prime.
*** Exception: 44623289911632568097011006112......7404020907669595372484820991 is not a prime.
*** Exception: 19322687615086291723476759454......4336733540374348490407411711 is not a prime.
*** Exception: 58418267242802372854733467471......1683206676499237077451276287 is not a prime.
*** Exception: 45694248869511749731339270259......1717409453665661424456695807 is not a prime.
*** Exception: 70464987632426004362292797550......8632700426437616126333550591 is not a prime.
*** Exception: 41458733762112420444199482867......8298992738570837806549041151 is not a prime.
*** Exception: 97602323201420798697706107356......9676091442066691089821073407 is not a prime.
*** Exception: 18635555394378846803544112604......5808269684026257542991577087 is not a prime.
*** Exception: 67060881961661014500261912652......5163752049785526783110545407 is not a prime.
*** Exception: 42815749646525926205600082959......5500798142909609824672022527 is not a prime.
*** Exception: 96963003772423585678984828780......8127578817493325346244657151 is not a prime

What does this mean?

Tessmore commented 11 years ago

Can we still add data for assignment 4?

For assignment 6: These numbers are just Mersenne numbers, but not Mersenne primes. It is data output from running testMP.

What exactly do we need to provide as "data" as output of our test is not sufficient?