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Recurrent sequences

                                                     Mina Šekularac
                                  Regional Talent Centre, Belgrade II, minasekularac@hotmail.com
        1.  Introduction
                                                               the reproduction of living organisms. Fibonacci was one of
         This paper deals with recurrent  sequences. The sequences   the most accomplished mathematicians of the Middle Ages.
         in  which  a  general  term  of  the  sequence  depends  on  its
         predecessors  are  recurrent  sequences.  The  concept  in   Arithmetic and geometric sequences
         mathematics and programming in which the same function
         is repeatedly applied in order to solve a problem is known   The  sequence  of  real  numbers,  where  each  consecutive
         as recursion. This mathematical process has been used since   member  is  found  by  adding  the  fixed  number     to  the
         XII century in order to provide solutions to various laws of   previous  member, is called arithmetic sequence. The term
         science.                                                  is  the  difference  of  the  sequence.  The  arithmetic
                                                               sequence corresponds to the relation:
                                                                                             , for              (1)

        2.  Working methods                                    The sequence where each member, starting from the second
                                                               one, is found by multiplying the previous one by the fixed
         The following research methods are to be applied in order   number    , is called geometrical sequence. The term     is
         to carry out the recurrent sequence research:         the  quotient.  Geometrical  sequence  corresponds  to  the
           data gathering  and analysis  using  the literature on this   recurrent formula:
            topic,                                                                          , for             (2)
           analysis of previous researches in this field,
           previous data processing and systematization,
           conclusion methods based on previous facts on general   Linear differential equation
            information.
                                                               Relation of the form:
         Research results regarding the recurrent sequences and their

         application  in  the  field  of  mathematics,  programming  and                                      (3)
         everyday  life,  will  be  summerized  and  presented  as  the
         mixture of previous information and the latest conclusions   for          (k is a constant and         ) is called linear
         based on this research.                               differential (recurrent) equation of order k.
                                                               Characteristic equation of the differential equation of order
                                                               k is the equation of order k:
        3.  Rеsearch results                                                                                                   (4)



         Sequences
                                                              4.  Conclusion
         If any natural number   , in accordance with some law of
         science,  corresponds  to  a  real  number    ,  it  is  a  never-  The researches on recurrent sequences have been conducted

         ending  sequence  of  real  numbers                   .  The   for  centuries.  In  addition  to  theoretical  and  practical



         numbers                   are the members of the sequence   significance in the field of mathematics and computational



                                                               science,  certain  chemical  reactions  are  carried  out  in
                   th
         and    is    member of general member of the sequence   accordance with the principle of recurrent sequences. When

             .                                                 it  comes  to  Nature,  the  process  of  reproduction  and  the

         Better known sequences:                               number  of  individuals  are  based  on  the  principles  of
         1°                          – the sequence of natural numbers,   recurrent sequence. Solving various IT problems is usually
                 is a general member of the sequence;          performed  by  continual  repetition  of  specific  methods
         2°                                    -  the  sequence  of  even   (functions).  The  application  of  recurrent  functions  has
             numbers,         is a general member of the sequence;   affected  the  development  of  computational  technologies
         3°                                 -  the  sequence  of  prime   and  led  to  improvement  of  modern  technological
             numbers;                                          achievements.


         4°              -  harmonious  sequence,      is  a  general

             member of the sequence;                           Literature
         5°                                  - The Fibonacci Sequence;
         6°  ...                                              [1.]  Z.  Kadelburg,  V.  Mićić,  S.  Ognjanović:  Analiza  sa
                                                                   algebrom  3  (Analysis  and  algebra),  Krug  Beograd,
         If the sequence      has the limiting value x, the sequence

               is convergent and it converges to x. If the sequence   2011.

               does  not  have  a  limiting  value,  then  the  sequence   [2.]  L.   Stefanović,   M.   Matejić,   S.   Marinković:

         diverges and it is divergent.                             Diferencijalne jednačine (Differential equations) , SKC
                                                                   Niš, 2006.
         Historical review of recurrent sequences             [3.]  L.  Stefanović:  Teorija  nizova  (Theory  of  Sequences),
                                                                   SKC Niš, 2010.
                                                         th
         The term recurrent equation was first mentioned in the 12
         century, in theoretical works of Leonardo Pisano, known as   [4.]  Murraz  Spiegel:  Calculus  of  Finite  Differences  and
                                                                   Difference Equations, Schaum, 1971.
         Fibonacci. He was exploring numerous scientific laws on
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