Definition:Cullen Number

Definition
A Cullen number is a positive integer of the form:
 * $n \times 2^n + 1$

Also defined as
Some sources refer to numbers of the form $n \times 2^n - 1$ as also being Cullen numbers.

However, it is now conventional to refer to numbers of the form $n \times 2^n - 1$ as Woodall numbers, for.

Also known as
Some sources refer to Cullen numbers as Cunningham numbers, for, so as to ensure their distinction from Woodall numbers.

Also see

 * Definition:Cullen Prime