MathDB
Turkey NMO 2010 P5

Source:

December 15, 2010
algebrapolynomialmodular arithmeticnumber theory proposednumber theory

Problem Statement

For integers aa and bb with 0a,b<2010180 \leq a,b < {2010}^{18} let SS be the set of all polynomials in the form of P(x)=ax2+bx.P(x)=ax^2+bx. For a polynomial PP in S,S, if for all integers n with 0n<2010180 \leq n <{2010}^{18} there exists a polynomial QQ in SS satisfying Q(P(n))n(mod201018),Q(P(n)) \equiv n \pmod {2010^{18}}, then we call PP as a good polynomial. Find the number of good polynomials.