Re: Sock Drawer - ans (a,b,c)
I stumbled across this thread via the more recent thread "Probability Problem (non-poker)."
BruceZ says we are solving t(t-1) = 2r(r-1).
irchans says he reads of a connection to Pell's equation: n x^2 + 1 = y^2 .
The connection is this. Let T=2t-1, R=2r-1.
Then t(t-1) = 2r(r-1) becomes 2R^2=T^2+1.
(I don't know how to solve these or what is known.)
|