For how many integers n is 2^y = y^2 ?
Choose one
A) None of these	B) One	C) Four	D) Three	E) More than four
draw a graph with y^2 and 2^y, you'll see 3 intercepts between the 2 curves, but one is in the 2nd quadrant, so it can't be an integer (for integer values of x, 2^x can be an integer only for x&gt;0). Thus 2 are valid, and the answer is None of these
<result>A</result>
For how many integers n is 2^y = y^2 ?