On integers not of the form ±𝑝^{𝑎}±𝑞^{𝑏}

In 1975 F. Cohen and J.L. Selfridge found a 94-digit positive integer which cannot be written as the sum or difference of two prime powers. Following their basic construction and introducing a new method to avoid a bunch of extra congruences, we are able to prove that if x ≡ 47867742232066880047611079 ( mod ⁡ 66483034025018711639862527490 ) , \begin{equation*} \hspace {-1.5pc} x\equiv 47867742232066880047611079 (\operatorname {mod} 66483034025018711639862527490), \hspace {-1.5pc} \end{equation*} then x x is not of the form ± p a ± q b \pm p^{a}\pm q^{b} where p , q p,q are primes and a , b a,b are nonnegative integers.