Learn how to say Subsequency correctly in English with this tutorial pronunciation video.
Oxford dictionary definition of the word subsequence:
the fact or state of being subsequent
a subsequent incident or occurrence
(ˌsʌbˈsiːkwəns) (mathematics) a sequence derived from a given sequence by selecting certain of its terms and retaining their order. Thus, a2, a3 is a subsequence of a1, a2, a3, while a3, a2 is not