olymmath

BALKAN-SL 2018 N1

    For positive integers mm and nn, let d(m,n)d(m, n) be the number of distinct primes that divide both mm and nn. For instance, d(60,126)=d(22×3×5,2×32×7)=2d(60,126)=d\left(2^{2} \times 3 \times 5,2 \times 3^{2} \times 7\right)=2. Does there exist a sequence (an)\left(a_{n}\right) of positive integers such that: (i) a1⩾20182018a_{1} \geqslant 2018^{2018}; (ii) am⩽ana_{m} \leqslant a_{n} whenever m⩽nm \leqslant n; (iii) d(m,n)=d(am,an)d(m, n)=d\left(a_{m}, a_{n}\right) for all positive integers m≠nm \neq n ? (United Kingdom)

    Dataset text NuminaMath olympiads. Quoted with source.

    Solutions

    No solution is on olymmath yet. Official and human solutions come first when they arrive. AI solutions come after them, with a label.

    Add a solution

    Locator balkan-sl/2018/n1 · Tag SH8YBXD6RA · Edit this page on GitHub · Keys: j next, k previous