HasAWholePowerPastTheFirstOf​(AngouriMath.​Entity,​AngouriMath.​Entity.​Variable)

Whether a factor of denominator is a whole power past the first of
something in x: what a rule for a power of a quadratic below the
bar needs, asked before the numerator is read. Under a substitution the numerator can
be a sum of exponentials brought over one bar, thousands of terms, and three such
rules expanded it in turn to be told it was not a polynomial -- six seconds each of
the inverse hyperbolic substitution for `x^4 (d + e x^2)^3 (a + b arcosh(c x))`, whose
denominator holds no x at all. https://github.com/asc-community/AngouriMath/issues/233