

A196446


Numbers n such that both n and (n1)^2*2^n1 are primes.


1



2, 3, 19, 29, 43, 61, 79, 109, 151, 167, 2311
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OFFSET

1,1


COMMENTS

Primes p such that (p1)^2*2^p1 is also prime.


LINKS

Table of n, a(n) for n=1..11.


EXAMPLE

a(1)=2 because 2 is a prime and (21)^2*2^21=3 is a prime,
a(2)=3 because 3 is a prime and (31)^2*2^31=31 is a prime,
a(3)=19 because 19 is a prime and (191)^2*2^191=169869313 is a prime,
a(4)=29 because 29 is a prime and (291)^2*2^291=420906795007 is a prime.


MATHEMATICA

Select[Prime[Range[40]], PrimeQ[(#1)^2 2^#1]&] (* The program generates the first 10 terms *) (* Harvey P. Dale, Sep 06 2017 *)


CROSSREFS

Sequence in context: A215383 A215387 A140555 * A265799 A058912 A040145
Adjacent sequences: A196443 A196444 A196445 * A196447 A196448 A196449


KEYWORD

nonn


AUTHOR

JuriStepan Gerasimov, Oct 02 2011


STATUS

approved



