単調 たんちょう減少 げんしょう数列 すうれつじゃなかったです
tanchōgenshō sū retsujanakattadesu

Noun
Desu Copula

The polite, past negative form of 単調減少数列

1. Wasn't a monotonically decreasing sequence.

Past/Perfective
Negative
Polite
Casual Register
Mathematics