Maths Olympiad Prep

Library / /126 of 151

, 2026

Algebra Difficulty 8.0 Shortlist Prove it Hungary

Let a0=0<a1<a2<<ana_0=0<a_1<a_2<\ldots<a_n be integers such that the sequence bk=ak+1ak2k+1b_k=\frac{a_{k+1}-a_k}{2k+1} (k=0k=0, 1, \ldots, n1n-1) is non-decreasing. Suppose that c1c_1, c2c_2, \ldots, cnc_n are real numbers such that the polynomial 1+k=1nckxak1+\sum_{k=1}^n c_kx^{a_k} is divisible by the polynomial (x+1)n(x+1)^n. Show that 2>c1>c2>>cn2>|c_1|>|c_2|>\ldots>|c_n|.

Want a route through all this instead of an archive? The track puts 2,000 problems in a working order, from AMC 10 level to the IMO shortlist.

Source: KöMaL, licensed Rights held by KöMaL and the MATFUND Foundation. Statement reproduced verbatim; metadata (topic, difficulty) added by this project. Solutions are the publisher's, linked not copied.