Problems

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Find \(m\) and \(n\) knowing the relation \(\binom{n+1}{m+1}: \binom{n+1}{m}:\binom{n+1}{m-1} = 5:5:3\).

Each side in the triangle \(ABC\) is divided into 8 equal segments. How many different triangles exist with the vertices at the points of division (the points \(A\), \(B\), \(C\) cannot be the vertices of triangles) in which neither side is parallel to either side of the triangle \(ABC\)?

How many integers are there from 1 to 1,000,000, which are neither full squares, nor full cubes, nor numbers to the fourth power?

Tickets cost 50 cents, and \(2n\) buyers stand in line at a cash register. Half of them have one dollar, the rest – 50 cents. The cashier starts selling tickets without having any money. How many different orders of people can there be in the queue, such that the cashier can always give change?

Prove that the Catalan numbers satisfy the recurrence relationship \(C_n = C_0C_{n-1} + C_1C_{n-2} + \dots + C_{n-1}C_0\). The definition of the Catalan numbers \(C_n\) is given in the handbook.

\(N\) points are given, no three of which lie on one line. Each two of these points are connected by a segment, and each segment is coloured in one of the \(k\) colours. Prove that if \(N > \lfloor k!e\rfloor\), then among these points one can choose three such that all sides of the triangle formed by them will be colored in one colour.

There are 4 weights and scales. How many loads that are different by weight can be accurately weighed using these weights, if

a) weights can be placed only on one side of the scales;

b) weights can be placed on both sides of the scales?