# R2F(1/2B1)S

Robert P. Munafo, 2008 Feb 28.

R2F(1/2B1)S is the largest island mu-molecule in the Mandelbrot Set. It is located on the real axis with its cusp at precisely -1.75.

The nucleus of R2F(1/2B1)S is given precisely by one of the
solutions to the equation Z_{3} = 0, where Z_{3} is the 3^{rd}
lemniscate. It is precisely:

(√23/(6 √3)-^{25}/_{54})^(^{1}/_{3})
+ 1/(9 (√23/(6 √3)-^{25}/_{54})^{(1/3)})
- ^{2}/_{3}

which works out to -1.754877667430458... + 0i.

R2-Name: | R2F(1/2B1)S |

Abbrev: | RF(2)S |

Colloq.: | Period-3 midget, largest island |

Coords: | center = -1.765+0i, size = 0.06 |

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R2F(1/2B1)S |

To the left of B: Location of figure 2 in the embedded Julia sets article.

Below C: Location of figure 3 in the embedded Julia sets article.

Like all islands, R2F(1/2B1)S is surrounded by a large collection of filaments that resemble the filament in which the island is contained. In this case, the filaments are straight. The shape of the filaments (long and straight with few side branches) allows for a minimum of clutter in both Distance Estimator and Dwell views, and also has the effect of reducing the Dwell Limit that is necessary for viewing various types of features.

Perhaps the most interesting features found near islands are the embedded Julia sets. Because R2F(1/2B1)S is the largest island, it has the largest embedded Julia Sets, and is thus the best place to explore them (particularly when zooming is limited by available computational accuracy).

Because R2F(1/2B1)S is on the real axis, it has mirror symmetry. Most islands do not. It is not just a scaled-down copy of R2; it has a trapezoid-shaped distortion that makes its eastward features larger and westward features smaller than their counterparts on R2. For example, R2F(1/2B1)SF(1/4B1)S is larger than R2F(1/2B1)S.1/2F(1/2B1)S, but R2F(1/4B1)S is smaller than R2.1/2F(1/2B1)S. See Mu-Molecule Metrics for further explanation of mu-molecule distortions.

The largest island that is a part of R2F(1/2B1)S's mu-unit is R2F(1/2B1)SF(1/2B1)S.

[1] See the footnote in the R2.1/3a entry for the Maxima code that gives the precise formula.

From the Mandelbrot Set Glossary and Encyclopedia, by Robert Munafo, (c) 1987-2020. Mu-ency index

This page was written in the "embarrassingly readable" markup language RHTF, and was last updated on 2020 Jan 15. s.11