If F(n) is a function that satisfies F(1)=F(2)=F(3)=1,with:
F(n+1)=(F(n)*F(n-1)+1)/F(n-2) whenever n>=3.
Find the value of F(6)
The point P lies on side CD of rectangle ABCD, with CD = 20 and AD = 10. The
circumcircle ω of △ABP re-intersects CD at Q. Given that the radius of ω is 11, find the distance
PQ.
Coins of diameter 1 have been placed in a square of side 11, without overlapping or protruding from the square. Can there be 126 coins? and 127? and 128?
