

A099051


p*2^p  1 where p is prime.


0



7, 23, 159, 895, 22527, 106495, 2228223, 9961471, 192937983, 15569256447, 66571993087, 5085241278463, 90159953477631, 378231999954943, 6614661952700415, 477381560501272575, 34011184385901985791
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OFFSET

1,1


COMMENTS

This is the subset of Woodall numbers of prime index. The 9th largest known Woodall prime is in this sequence: 12379*2^123791, where 12379 is prime, as found by Wilfrid Keller in 1984. Smaller primes are when p = 2, 3, 751. These numbers can also be semiprime, as when p = 159, 163, or 211 and hard to factor as when n = 349 (108 digits).  Jonathan Vos Post, Nov 19 2004


REFERENCES

Ribenboim, P. The New Book of Prime Number Records. New York: SpringerVerlag, pp. 360361, 1996


LINKS



EXAMPLE

If p=3, 3*2^3  1 = 23.
If p=11, 11*2^11  1 = 22527.


MATHEMATICA



CROSSREFS



KEYWORD

nonn,easy


AUTHOR



EXTENSIONS



STATUS

approved



