English
The half-closed interval Ico(a,b) is the set of x with a ≤ x and x < b; i.e., Ico(a,b) = {x | a ≤ x ∧ x < b}.
Русский
Полуоткрытый интервал Ico(a,b) состоит из x, обладающих a ≤ x и x < b; то есть Ico(a,b) = {x | a ≤ x ∧ x < b}.
LaTeX
$$$Ico(a,b) = \{x \mid a \le x \land x < b\}$$$
Lean4
/-- `Ico a b` is the left-closed right-open interval $[a, b)$. -/
def Ico (a b : α) :=
{x | a ≤ x ∧ x < b}