IMO 1995 Shortlist

IMO 1995 Shortlist — 28 problems. Algebra (6) · Geometry (8) · Number Theory (8).

28 items

IMO 1995 Shortlist

28 problems · Source: IMO Compendium

Algebra

# Origin Problem
A1 RUS Let a, b, and c be positive real numbers such that abc = 1.
A2 SWE Let a and b be nonnegative integers such that ab \geqc2,
A3 UKR Let n be an integer, n \geq3. Let a1, a2, . . . , an be real numbers
A4 USA Let a, b, and c be given positive real numbers. Determine all
A5 UKR Let R be the set of real numbers. Does there exist a function
A6 JAP Let n be an integer, n \geq3. Let x1, x2, . . . , xn be real numbers

Geometry

# Origin Problem
G1 BUL Let A, B, C, and D be distinct points on a line, in that
G2 GER Let A, B, and C be noncollinear points. Prove that there is
G3 TUR The incircle of ABC touches BC, CA, and AB at D, E, and
G4 UKR An acute triangle ABC is given. Points A1 and A2 are taken
G5 NZL Let ABCDEF be a convex hexagon with AB = BC =
G6 USA Let A1A2A3A4 be a tetrahedron, G its centroid, and
G7 LAT O is a point inside a convex quadrilateral ABCD of area
G8 COL Let ABC be a triangle. A circle passing through B and C in-

Number Theory

# Origin Problem
N1 ROM Let k be a positive integer. Prove that there are infinitely
N2 RUS Let Z denote the set of all integers. Prove that for any integers
N3 CZE Determine all integers n > 3 such that there are n points
N4 BUL Find all positive integers x and y such that x+y2+z3 = xyz,
N5 IRE At a meeting of 12k people, each person exchanges greetings
N6 POL Let p be an odd prime. Find the number of p-element
N7 BLR Does there exist an integer n > 1 that satisfies the following
N8 GER Let p be an odd prime. Determine positive integers x and

Problems

# Origin Problem
23 S1 (UKR) Does there exist a sequence F(1), F(2), F(3), . . . of nonneg-
24 S2 (POL)IMO4 The positive real numbers x0, x1, . . . , x1995 satisfy x0 =
25 S3 (POL) For an integer x \geq1, let p(x) be the least prime that does not
26 S4 (NZL) Suppose that x1, x2, x3, . . . are positive real numbers for which
27 S5 (FIN) For positive integers n, the numbers f(n) are defined induc-
28 S6 (IND) Let N denote the set of all positive integers. Prove that there