Four prime squares and powers of 2
Four squares of primes and 165 powers of 2
Four squares of primes and powers of 2
By developing the method of Wooley on the quadratic Waring-Goldbach problem, we prove that all sufficiently large even integers can be expressed as a sum of four squares of primes and 46 powers of 2.
Further improvements in Waring's problem, IV: Higher powers