Primorial

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Definition

Let be a natural number. The primorial, sometimes denoted , is defined as the product of the first prime numbers.

The primorial is defined to be .

An alternate definition of primorial, called here the primorial of the second kind, is defined as the product of all the primes less than or equal to a given number. Note that the logarithm of the primorial of the second kind is the first Chebyshev function.

Occurrence

Initial values

The values of primorials at are given in the list: 1, 2, 6, 30, 210, 2310 View list on OEIS

Special properties