a sequence a0, a1 a2, … that satisfies a relationship in the form
an + p + C1an + p - 1 + … + Cpan = 0
where C1, … ,Cp are constants. This relationship makes it possible to calculate, one after another, the members of the sequence if the first p members are known. The Fibonacci sequence 1, 1, 2, 3, 5, 8, … (a0 = 1, a1 = 1, …, an + 2 = an + i + an) is a classical example of a recurrent sequence. The origin of the term “recurrent sequence” is associated with the name of A. de Moivre, who regarded power series a0 + a1x + a2x2 … with coefficients forming a recurrent sequence as being “recurrent series.” Such series always portray rational functions.