1. A sequence-program-component creation program that causes a computer to perform: a searching step of searching an overall circuit of a sequence program for a common logic part and extracting a logic pattern that appears in common in a circuit pattern arranged in the common logic part as a common circuit pattern; a component-candidate displaying step of displaying an extracted common circuit pattern as a candidate for a program component; a component registration setting step of registering a common circuit pattern selected by a user from candidates for the program component; and a replacing step of replacing the common logic part of the sequence program with the program component, wherein at the searching, the common logic part is searched using a number of first circuit blocks specified by a user as a search unit.