# How many pairs?

How many ordered pairs $$(x,y)$$ are there with $$x \in \{0,1,2, \ldots, 25\},$$ $$y \in \{0,2,4,\ldots, 50\}$$ and $$x < y?$$

Details and assumptions

For an ordered pair of integers $$(a,b)$$, the order of the integers matter. The ordered pair $$(1, 2)$$ is different from the ordered pair $$(2,1)$$.

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