Given that there are exactly four primes that divide the number

257⁴ + 32³ - 8193² - 640²

find the largest of the four primes.

>> n=257^4 + 32^3 - 8193^2 - 640^2
n =
                4294968320
>> factortable(n)
ans =
          10           2
           1           5
           1         397
           1        2113

function ft=factortable(x)
  f1=factor(x);
  f1=f1';
  [ft1, ft2]=groupcounts(f1);
  ft=[ft1 ft2];
end

Posted by Charlie on 2024-12-12 10:55:02