文摘
For integers k,n,ck,n,c with k,n≥1k,n≥1, the nn-color Rado number Rk(n,c)Rk(n,c) is defined to be the least integer NN if any, or infinity otherwise, such that for every nn-coloring of the set {1,2,…,N}{1,2,…,N}, there exists a monochromatic solution in that set to the linear equation x1+x2+⋯+xk+c=xk+1.A recent conjecture of ours states that Rk(n,c)Rk(n,c) should be finite if and only if every divisor d≤nd≤n of k−1k−1 also divides cc. In this paper, we complete the verification of this conjecture for all k≤7k≤7. As a key tool, we first prove a general result concerning the degree of regularity over subsets of ZZ of some linear Diophantine equations.