A Woodall number is a number of the form W_n = 2^n n - 1. Woodall numbers are therefore similar to Mersenne numbers 2^n - 1 but with an additional factor of n multiplying the power of 2, and to Cullen numbers 2^n n + 1 but with the sign flipped. For n = 1, 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

Allan Joseph Champneys Cunningham | Hans Riesel | H. J. Woodall