
 A+B=C
 Hats 0 to n1, someone to be right
 Perrin
 Product of chords
 Counting bounces
 Pythagoras by incircle
 Astronaut in a sphere
 Coins to make hexagon
 Coins to make straight line
 Brownian, (0,1) > (<1,0) prob?
 Tethered to perimeter, graze half?
 Sqrt 2 not in Q. n^th root neither
 Mutilated chessboard
 Thirteen piles of four.
 Three integers in a.p. whose product is prime?
 Integer whose English name is alphabetical?
 Lifting the rail track
 Curve versus triangle

 Infinitely many composites
 Shoelaces  knot theory
 sin t + a cos (t+c) is still sin
 Product of sum of squares still
 Half integer rectangles
 Pythagoras generalised
 Non crossing Euler.
 Bicolour Jordan curves.
 Complex proof of Pythagoras
 Unstable quadratics
 Why is A4 210x297 ?
 Area by cutout and weigh.
 Percentage wine in water.
 Tower of a's
 Lanchester's laws
 Rock in boat in swimming pool
 helium balloon in car
 Cars across the desert
