# Problem 566: Cake Icing Puzzle
Adam plays the following game with his birthday cake. He cuts a piece
forming a circular sector of 60 degrees and flips the piece upside down,
with the icing on the bottom. He then rotates the cake by 60 degrees
counterclockwise, cuts an adjacent 60 degree piece and flips it upside
down. He keeps repeating this, until after a total of twelve steps, all
the icing is back on top. Amazingly, this works for any piece size, even
if the cutting angle is an irrational number: all the icing will be back
on top after a finite number of steps. Now, Adam tries something
different: he alternates cutting pieces of size \$x=\\frac{360}{9}\$
degrees, \$y=\\frac{360}{10}\$ degrees and \$z=\\frac{360
}{\\sqrt{11}}\$ degrees. The first piece he cuts has size x and he flips
it. The second has size y and he flips it. The third has size z and he
flips it. He repeats this with pieces of size x, y and z in that order
until all the icing is back on top, and discovers he needs 60 flips
altogether. Let F(a, b, c) be the minimum number of piece flips needed
to get all the icing back on top for pieces of size \$x=\\frac{360}{a}\$
degrees, \$y=\\frac{360}{b}\$ degrees and \$z=\\frac{360}{\\sqrt{c}}\$
degrees. Let \$G(n) = \\sum\_{9 \\le a < b < c \\le n} F(a,b,c)\$,
for integers a, b and c. You are given that F(9, 10, 11) = 60,
F(10, 14, 16) = 506, F(15, 16, 17) = 785232. You are also given
G(11) = 60, G(14) = 58020 and G(17) = 1269260. Find G(53).