- --- In primenumbers@yahoogroups.com, Kevin Acres <research@...> wrote:

> after now having found 17 15/16 chains, should

Suppose that you guessed a 1/9 chance. Then the odds

> I reasonably be expecting a 16/16 some time soon?

of /not/ getting a result after 17 tries are

exp(-17/9) =~ 15%

David - --- In primenumbers@yahoogroups.com,

Kevin Acres <research@...> wrote:

> x=a*x+b either is a square or has a square as a major factor.

Suppose that we want to start with a square and get a square.

Then we must solve the Diophantine equation

y^2 = a*x^2 + b

For any pair (a,b), Dario will tell us all the solutions:

http://www.alpertron.com.ar/QUAD.HTM

David