MathDB

3

Part of 2002 Switzerland Team Selection Test

Problems(1)

d_1^2+d_2^2+d_3^2+d_4^2 = n

Source: Switzerland - Swiss TST 2002 p3

2/18/2020
Let d1,d2,d3,d4d_1,d_2,d_3,d_4 be the four smallest divisors of a positive integer nn (having at least four divisors). Find all nn such that d12+d22+d32+d42=nd_1^2+d_2^2+d_3^2+d_4^2 = n.
Divisorsnumber theorySum