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Equation 2 · Part 1 · The Valley of Stability Is a Fitness Landscape

Symbol Z

ZZ
ZZ

What this part means

the proton number.

Its job in the formula

Z is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.

Where the article explains it

Each point is a pair of integers, a proton number Z and a neutron number N , and at each occupied point sits one nuclear species with a measured or estimated mass.

The passage around this formula

That chart is a discrete space. Each point is a pair of integers, a proton number Z and a neutron number N , and at each occupied point sits one nuclear species with a measured or estimated mass. The 2020 evaluation of nuclear structure and decay properties, NUBASE2020, lists recommended ground-state properties for 3,340 nuclides, plus a further 1,938 excited isomeric states,…

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Learn the underlying idea

A variable is a named place for a value. Its letter is a local label: x can mean position in one formula and a data point in another.

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Sources cited in the surrounding passage

These citations provide research context; check each source for the exact claim it supports.