What is the generating function for the sequence 1,1,1,1,dots1, 1, 1, 1, \\dots1,1,1,1,dots?
fracx1−x\\frac{x}{1-x}fracx1−x
frac1(1−x)2\\frac{1}{(1-x)^2}frac1(1−x)2
frac11−x\\frac{1}{1-x}frac11−x
frac11+x\\frac{1}{1+x}frac11+x