2017/02/15 by Izadi, Farzali, Baghalaghdam, Mehdi
#FOS: Mathematics #Number Theory (math.NT)
paper · doi:10.48550/arxiv.1702.08500
In this paper, elliptic curves theory is used for solving the Diophantine equations X3+Y3+Z3+aUk=a0U0t0+...+anUntn, k=3,4 where n, ti are natural numbers and a, ai are fixed arbitrary rational numbers. We try to transform each case of the above Diophantine equations to a cubic elliptic curve of positive rank, then get infinitely many integer solutions for each case. We also solve these Diophantine equations for some values of n, a, ai, ti, and obtain infinitely many solutions for each case, and show among the other things that how sums of four, five, or more cubics can be written as sums of four, five, or more biquadrates as well as sums of 5th powers, 6th powers and so on.