there are quite a few look-up table solutions, could you perhaps add something like the following to the test suite to discourage these? assert(~any(cellfun(@(x)ismember(max([0,str2num(x)]),[51,2485,136162,8578934]),regexp(fileread('pairPrimes.m'),'[\d\.\+\-\*\/]+','match'))))
Do you consider (13, 31) and (31, 13) as the same or different pair primes? Similarly, how about (79, 97) and (97, 79)?
Thanks for pointing it out. They are different pair primes.
Good problem. At first, I thought we needed to reverse the numbers, but only their order is necessary. And we need to count twice numbers like 31 and 13.
can you do better than this?
surface of a spherical planet
Project Euler: Problem 7, Nth prime
Back to basics 9 - Indexed References
07 - Common functions and indexing 6
Inscribed Pentagon? 2
Is there a GPU Device?
Repeat string n times
Lunar Arithmetic (Multiplication)
Net Present Value of a Stream of Cash Flows
Make visible max values
Choose a web site to get translated content where available and see local events and offers. Based on your location, we recommend that you select: .
You can also select a web site from the following list:
Select the China site (in Chinese or English) for best site performance. Other MathWorks country sites are not optimized for visits from your location.
Contact your local office