A beautiful sunny Sunday in Seattle.  Outside my window, ships go through the
locks, salmon swim up the ladder, a bagpipe band plays in the garden and I am
inside coding.  Actually I love coding.  And I have kept it down to two hours.

NEW_mandelx_pattern was identified all along as a hack.  Perfectly adequate for
demonstrating the improved power computations, but for timing purposes
representing a worst-case promise rather than any basis for quantitative
comparison.

NEWER_mandelx_pattern is a speed-optimized version.  Ready for quantitative
comparisons.  My main avenue of attack was to unroll my awful interior loops.
Short, badly branch-predicted.  Ideal candidates.  The measured result is
posted among the images.

Also I have extended NEWER_mandelx_pattern to treat exponents up to 255.

The old mandel_pattern.  A fine code.  I would have said speed optimal, in fact.
 I was hoping to come within 10% of its speed.    But the measurements are
showing NEWER_mandelx_pattern to be 6.8% FASTER, for some unexpected reason.  I
will not be satisfied until I have tracked down why this is.

Will post NEWER_mandelx_pattern after I understand it vs. mandel_pattern and
prune its code way down.

Algo

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