Let k be an integer ≥ 2 \geq 2 and p a prime such that v k ( p ) = ( k , p − 1 ) > 1 {v_k}(p) = (k,p - 1) > 1 . Let b n + c ( n = 0 , 1 , … ; b ≥ 2 , 1 ≤ c > b , ( b , p ) = ( c , p ) = 1 ) bn + c(n = 0,1, \ldots ;b \geq 2,1 \leq c > b,(b,p) = (c,p) = 1) be an arithmetic progression. We denote the smallest kth power nonresidue in the progression b n + c bn + c by g ( p , k , b , c ) g(p,k,b,c) , the smallest quadratic residue in the progression b n + c bn + c by r 2 ( p , b , c ) {r_2}(p,b,c) , and the nth smallest prime kth power nonresidue by g n ( p , k ) , n = 0 , 1 , 2 , … {g_n}(p,k),n = 0,1,2, \ldots . If C ( p ) C(p) is the multiplicative group consisting of the residue classes mod p \bmod \;p , then the kth powers mod p \bmod \;p form a multiplicative subgroup, C k ( p ) {C_k}(p) . Among the v k ( p ) {v_k}(p) cosets of C k ( p ) {C_k}(p) denote by T the coset to which c belongs (where c is the first term in the progression b n + c ) bn + c) , and let h ( p , k , b , c ) h(p,k,b,c) denote the smallest number in the progression b n + c bn + c which does not belong to T so that h ( p , k , b , c ) h(p,k,b,c) is a natural generalization of g ( p , k , b , c ) g(p,k,b,c) . We prove by purely elementary methods that h ( p , k , b , c ) h(p,k,b,c) is bounded above by 2 7 / 4 b 5 / 2 p 2 / 5 + 3 b 3 p 1 / 5 + b 2 {2^{7/4}}{b^{5/2}}{p^{2/5}} + 3{b^3}{p^{1/5}} + {b^2} if p is a prime for which either b or p − 1 p - 1 is a kth power nonresidue. The restriction on b and p − 1 p - 1 may be lifted if p > ( g 1 ( p , k ) ) 7.5 p > {({g_1}(p,k))^{7.5}} . We further obtain a similar bound for r 2 ( p , b , c ) {r_2}(p,b,c) for every prime p, without exception, and we apply our results to obtain a bound of the order of p 2 / 5 {p^{2/5}} for the nth smallest prime kth power nonresidue of primes which are large relative to Π j = 1 n − 1 g j ( p , k ) \Pi _{j = 1}^{n - 1}{g_j}(p,k) .
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