2
Part of 2011 Bundeswettbewerb Mathematik
Problems(2)
16 children are sitting at a round table
Source: Germany Federal - Bundeswettbewerb Mathematik 2011, round 1, p2
4/10/2020
children are sitting at a round table. After the break, they sit down again on table. They find that each child is either sitting on its original [lace or in one of the two neighboring places. How many seating arrangements are possible in this way after the break?
combinatorics
3n + 1 and 10n + 1 are perfect squares , then 29n+11 not prime
Source: Germany Federal - Bundeswettbewerb Mathematik 2011, round 2, p2
4/15/2020
Proove that if for a positive integer , both and are perfect squares , then is not a prime number.
number theoryprimeCompositecomposite numberPerfect SquaresPerfect Square