The way this problem is stated is that you put 1 grain of rice on the first square, the second square has 2 grains of rice. The third square has 4 grains of rice and you keep on doubling from there. When you tell me there is a 0 square, I'm not sure what you mean.
That would mean (to me) that square 1 has 2 grains of rice
Square 2 has 4 grains of rice
Square 3 has 8 grains of rice
The table goes up to 64 squares on a chess board.
2^64 which is (rounded) to about 1.84 with 17 zeros behind the 1.84.
My calculator says the answer is 1.84 * 10^19
I think you want
2^64<<<<<answer.
Or maybe
y =R(x) = 2^x <<<< answer.
where the domain is 0 <=x <= 64 contained in the integers.