Concept

Rotational symmetry — where it appears

4 essays name this object, across 2 fields. What follows is each of them, and the objects they name alongside it.
5/107.9%5 × 1/23/67.9%3 × 1/22/46.1%2 × 1/24/85.5%4 × 1/27/145.2%7 × 1/26/122.8%6 × 1/28/160.1%8 × 1/2share of divergences at this riserise 0.008 · 3600 divergences35.4% share a factor

What "whorled" was hiding

The expansion phase's census put 35% of divergences in a bucket labelled whorled and moved on. Opened, every pair in it is k and 2k — the coarsest rung of the ladder, repeated k times — and reading the census up to jugacy takes the Fibonacci share from 14.7% to 50.1% without describing a single extra plant.

wrong · jugate census
1 at a time2 and 3symmetry order 12 at a time2 and 4symmetry order 23 at a time3 and 6symmetry order 3divergences 137.51° · 68.75° · 45.84°counted 2/3 · 2/4 · 3/6

Two at a time

Every counter on this site asks how far it is from element i to element i plus m, and that index is a claim that the elements arrived one at a time. For teasel, for Cephalaria and for a real minority of plants the claim is false — and what those patterns turn out to be is an ordinary lattice, wrapped twice.

lattices · jugacy
4 chains · counted pair 4 and 62-jugate at 69.35° · rise 0.064 chains in this family

Counting without an index

A person counting spirals on a cone puts a finger on one scale, follows a family round, and counts how many distinct chains there are. That needs no order of arrival — and building it turns out to be strictly more general than the counter the site had, and to find a bug in the counting of a bijugate stem that no assertion would have caught.

lattices · chain counting
plants show consecutive Fibonacci pairs far more…4and more often even than a coin weighted to a half14a conifer cone's rings are spaced as a cone rather…1multijugate patterns are a real minority rather than…34against 14.7%, if the truth is 90%needs: the pair, at a stated rungagainst 14.7%, if the truth is 50%needs: the pair, at a stated rungagainst φ² = 2.62, if the truth is φ^(2/1.88) = 1.67needs: three ring positions, to ±3%against 2%, if the truth is 15%needs: the pair; the whorl's symmetryspecimens neededexact binomial · α = 0.05 · power 0.91 to 34 specimens

The survey this site cannot do

Four phases of asking for a dataset, and it is still not here. What this phase can do instead is specify it — the fields, the sampling, the sizes, and which of this collection's claims each one would settle. Two of the four fields asked for turn out to be worth less than the asking implied, and one was never asked for at all.

wrong · survey spec

Named alongside it

The objects these essays reach for when they reach for this one.

JugacyRiseCensusBijugateCylinderFibonacciSurveyWhorlCounting blindBranchChain countingClassification

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