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The method of finding prime numbers without computer calculation is shown. Subsets P1 = {6k1 – 1}, P2 = {6k2 + 1}, Q1 = {6j1 – 1}, Q2 = {6j2 + 1} are considered, where P1 È P2 are all prime numbers p ≥ 5; Qi are all odd composite numbers of such form. Subsets Ai = {ki},...

It is shown that the first four primes 2, 3, 5, 7 generate finite subsets of primes, assuming the principle of interchangeability. In is established that any prime p(11 p 41, p  19), added together with two preceding primes generates a prime and that any prime p (5 p 31, p  13),...

... progression of the power k  and difference d is given. For k  1,7 formulas of nth member of such progressions and for k  1, 2, 3 formulas for the sum of the first n its members are obtained. Progressions ( ) , k p d M with the first member prime number p and difference being a positive even number d  2m (m  ) are considered. Such progressions define subsets ( ) , , k h p d M of h prime numbers (h  ). For k  20, p  95467, d  108 all subsets (1) h,p,d M with h  15 prime ...

Mould fungi are of particular interest as metal destroying microorganisms. This paper presents the results of a study on a number of organic compounds as St3 steel corrosion inhibitors and fungicides against the Aspergillus niger. Electrochemical, microbiological and gravimetric analyses helped increase the protective action of modified primer on steel corroding under the effect of Aspergillus niger. 1. Кузнецов М.   В. Противокоррозионная защита трубопроводов...

... infinite set of nu­merical properties of a right-angled Pascal triangle is confirmed and the main results of finding its numerical discriminant are given. Exactly, the numerical properties of the truncated Pascal triangle for the direct finding of all primes are found. Sherban V. L. Pascal triangle, Fibonacci numbers, prime numbers, recurrent se­quences 23-39