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# Woodall Number

A Woodall number is a number of the form

Woodall numbers are therefore similar to Mersenne numbers but with an additional factor of multiplying the power of 2, and to Cullen numbers but with the sign flipped.

For , 2, ..., the first few Woodall numbers are 1, 7, 23, 63, 159, 383, ... (OEIS A003261).

A Woodall number that is prime is known as a Woodall prime.

Cullen Number, Cunningham Number, Fermat Number, Integer Sequence Primes, Mersenne Number, Sierpiński Number of the First Kind, Thâbit ibn Kurrah Number, Woodall Prime

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## References

Cunningham, A. J. C. and Woodall, H. J. "Factorisation of and ." Messenger Math. 47, 1-38, 1917.Ribenboim, P. The New Book of Prime Number Records. New York: Springer-Verlag, pp. 360-361, 1996.Sloane, N. J. A. Sequence A003261/M4379 in "The On-Line Encyclopedia of Integer Sequences."

Woodall Number

## Cite this as:

Weisstein, Eric W. "Woodall Number." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/WoodallNumber.html