Definition:Dudeney Number

Definition

A Dudeney number is a natural number which is equal to the sum of the digits of its cube when expressed in decimal notation.

Sequence of Dudeney Numbers

The only Dudeney numbers are:

$0, 1, 8, 17, 18, 26, 27$

two of which are themselves cubes, and one of which is prime.

Also see

• Results about Dudeney numbers can be found here.

Source of Name

This entry was named for Henry Ernest Dudeney.

Historical Note

The natural numbers now referred to as Dudeney numbers were identified by Claude Séraphin Moret-Blanc in $1879$, although exactly where this was published is still to be identified.

Henry Ernest Dudeney picked up on it, and subsequently published it as $69$ - Root Extraction in his Modern Puzzles of $1926$.

The first appearance of the term Dudeney number has not been established, but it appears to be a recent coining.