title: An exact formula for the number of alignments between two DNA sequences.
abstract: Given two DNA sequences, one is usually interested in measuring their similarity. For this purpose we have to consider different alignments of both the sequences. The number of alignments grows rapidly with the length of the sequences. In this short communication, we give an exact formula for the number of possible alignments using the theory of difference equations.
authors.affiliation: Departamento de Psiquiatría, Radiología y Salud Pública, Facultad de Medicina, Universidad de Santiago de Compostela, Santiago de Compostela, Spain.
authors.forename: Angela
authors.initials: A
authors.lastname: Torres
authors.forename: Alberto
authors.initials: A
authors.lastname: Cabada
authors.forename: Juan J
authors.initials: JJ
authors.lastname: Nieto
mesh_terms: D000465:Algorithms; D001483:Base Sequence; D008962:Models, Theoretical; D016415:Sequence Alignment / Q000379:methods*