User blog comment:Hyp cos/Googolisms hard to extend?/@comment-28606698-20191225125521

That’s a recursive extension for the googologism based on Poincare recurrence time:

T(0)= Poincare recurrence time for black hole with radius equal to the radius of the observable universe,

T(n+1)= Poincare recurrence time for black hole with radius R=T(n)*c, where c is the speed of light.

Note that Poincare recurrence time for a black hole is equal to exp(exp(4π*M^2)),

where M=R*(c^2)/(2*G) is the mass of the black hole and G is the gravitational constant.

Then, T(n+1)= exp(exp(4π*( T(n)*(c^3)/(2*G))^2))