IMO 1983 Shortlist

IMO 1983 Shortlist — 25 problems. 25 problems.

25 items

IMO 1983 Shortlist

25 problems · Source: IMO Compendium

Problems

# Origin Problem
1 AUS The localities P1, P2, . . . , P1983 are served by ten international
2 BEL Let n be a positive integer. Let \sigma(n) be the sum of the natural
3 BEL We say that a set E of points of the Euclidian plane is
4 BEL On the sides of the triangle ABC, three similar isosceles tri-
5 BRA Consider the set of all strictly decreasing sequences of n natural
6 CAN Suppose that {x1, x2, . . . , xn} are positive integers for which
7 CAN Let a be a positive integer and let {an} be defined by a0 = 0
8 SPA In a test, 3n students participate, who are located in three
9 USA If a, b, and c are sides of a triangle, prove that
10 FIN Let p and q be integers. Show that there exists an interval I of
11 (FIN 2′) Let f : [0, 1] \toR be continuous and satisfy:
12 GBR Find all functions f defined on the positive real numbers
13 LUX Let E be the set of 19833 points of the space R3 all three
14 POL Prove or disprove: From the interval [1, . . . , 30000] one
15 POL Decide whether there exists a set M of natural numbers satis-
16 GDR Let F(n) be the set of polynomials P(x) = a0+a1x+\cdot \cdot \cdot+anxn,
17 GDR Let P1, P2, . . . , Pn be distinct points of the plane, n \geq2. Prove
18 FRG Let a, b, c be positive integers satisfying (a, b) = (b, c) =
19 ROM Let (Fn)n\geq1 be the Fibonacci sequence F1 = F2 = 1, Fn+2 =
20 ROM Solve the system of equations
21 SWE Find the greatest integer less than or equal to 21983
22 SWE Let n be a positive integer having at least two different prime
23 USS Let K be one of the two intersection points of the circles W1
24 USS Let dn be the last nonzero digit of the decimal representation
25 USS Prove that every partition of 3-dimensional space into three