My intuition is that F(x) = x^2 + 1 is supercritical. Jim On Sunday, June 17, 2018, Warren D Smith <warren.wds@gmail.com> wrote:
If in your process instead of doubling & add 1, i.e. the map 2x+1, do the map "F(x)" for integer polynomials F I would guess for fast enough growing F(x) the process ought to blow to create an infinite set of primes while for slow enough F it will not.
I.e. I suspect there is a "critical mass" phenomenon where at some point you are breeding new primes fast enough to create exponential population explosion, but below that point it self-limits.
So what sort of growth for F constitutes that "critical mass"? Interesting & likely delicate question.
Just as an initial guess, perhaps F(X) = 1 + X^floor(lnlnX) is supercritical, but F = any polynomial(X) is subcritical.
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