Definition:Plastic Constant

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The plastic constant is the real root of the cubic:

$x^3 - x - 1 = 0$

Its value is approximately:

$P = 1 \cdotp 32471 \, 795 \ldots$

This sequence is A060006 in the On-Line Encyclopedia of Integer Sequences (N. J. A. Sloane (Ed.), 2008).

Also known as

The plastic constant is also known as:

the plastic number
the plastic ratio
the minimal Pisot number
the platin number
the silver number (not recommended as there is another constant with that name)
Siegel's number (for Carl Ludwig Siegel)
le nombre radiant (French for the radiant number).

Some sources identify it with the symbol $\rho$.

Also see