The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A050918 Woodall primes: primes of form k*2^k-1. 16

%I

%S 7,23,383,32212254719,2833419889721787128217599,

%T 195845982777569926302400511,4776913109852041418248056622882488319,

%U 1307960347852357218937346147315859062783,225251798594466661409915431774713195745814267044878909733007331390393510002687

%N Woodall primes: primes of form k*2^k-1.

%H M. F. Hasler, <a href="/A050918/b050918.txt">Table of n, a(n) for n = 1..15</a> (all terms < 10^999).

%H Ray Ballinger, <a href="http://web.archive.org/web/20161028080439/http://www.prothsearch.net/woodall.html">Woodall Primes: Definition and Status</a>

%H C. K. Caldwell, <a href="http://primes.utm.edu/glossary/page.php?sort=WoodallNumber">Woodall Numbers</a>

%H Brady Haran and Matt Parker, <a href="https://www.youtube.com/watch?v=PQDvEJFdY1U">383 is cool</a>, Numberphile video, 2017.

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/WoodallNumber.html">Woodall Number</a>

%F a(n) = A002234(n)*2^A002234(n) - 1. - _M. F. Hasler_, May 10 2017

%t Select[Table[n 2^n - 1, {n, 300}], PrimeQ] (* _Harvey P. Dale_, Jul 12 2012 *)

%o (PARI) for(n=2,999,ispseudoprime(p=n*2^n-1)&&print1(p",")) \\ _M. F. Hasler_, May 10 2017

%Y Cf. A002234, A003261.

%K nonn,easy,nice

%O 1,1

%A _N. J. A. Sloane_, Dec 30 1999

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified May 9 07:36 EDT 2021. Contains 343692 sequences. (Running on oeis4.)