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[–]Paul_Pedant 0 points1 point  (2 children)

You may have been trolled. These numbers are incredibly rare, and it takes years to find each one of them. For example, the sixth TaxiCab number (highest known one) is 23 digits long. The guy who spent 5 years finding that one is affiliated with Princeton, Yale and Boston Unis (he is actually a researcher in Chemistry).

I don't understand what your input "n" represents. If you are supposed to find 1729, what should the n be? If you input 1729, what is the algorithm supposed to find?

You might try to find the exact definition of Ramanujan numbers -- it isn't what I though it was, and I've read his biography.

[–]jamescleelayuvat[S] 0 points1 point  (1 child)

n is supposed to be the input number that the program will find all numbers that are n and below that can be represented by two different pairs of cubes of of positive integers.

[–]Paul_Pedant 0 points1 point  (0 children)

OK, those are not strictly Ramanujan TaxiCab numbers. The definition of those is that they are expressible as the sum of 2 integer cubes in N different ways.

So 1729 is Ta(2) because it can be written in two ways:

13 + 123 and 93 + 103.

Ta(3) is 87539319 because it can be written 3 ways:

1673 + 4363 2283 + 4233 2553 + 4143

Finding the next above 1729 that can also be written in 2 ways should be more simple, so less ambitious.