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be a positive integer. A Japanese triangle consists of 
circles arranged in an equilateral triangular shape such that for each 
, 
, 
, , the 
row contains exactly 
circles, exactly one of which is coloured red. A ninja path in a Japanese triangle is a sequence of circles obtained by starting in the top row, then repeatedly going from a circle to one of the two circles immediately below it and finishing in the bottom row. Here is an example of a Japanese triangle with 
, along with a ninja path in that triangle containing two red circles., find the greatest 
such that in each Japanese triangle there is a ninja path containing at least red circles.
+1 w
, such that 
and 
.
such that 
is prime, 
with 
and ?
be a function such that for every regular 
-gon 
we have 
. Prove that 
for all reals 
.
inscribed in a circle, 
. On the side 
, point 
is marked so that 
. Prove that the perpendicular bisector of the segment 
bisects the arc 
that does not contain point 
.
inscribed in a circle, . On the side , point is marked so that . Prove that the perpendicular bisector of the segment bisects the arc that does not contain point .
