\lvertneqq
The symbol \lvertneqq is used in mathematical expressions to denote 'is not less than or equal to'. It is a negated relation symbol that is used to express that one quantity is strictly greater than another, without the possibility of equality.
x is strictly greater than y, not less than or equal to y.
x \lvertneqq y
The square of a is strictly greater than the square of b.
a^2 \lvertneqq b^2
n is strictly greater than m + 1, not less than or equal to m + 1.
n \lvertneqq m + 1