login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A075752 210*n -/+ 17 ares both primes. 1

%I #12 Sep 08 2022 08:45:07

%S 1,3,4,7,8,9,22,26,32,42,45,46,52,56,57,58,62,70,75,79,81,84,86,87,96,

%T 99,100,101,103,111,129,139,142,143,146,166,178,179,185,191,196,200,

%U 201,202,216,217,234,235,240,241,252,253,260,265,267,276,294,295,298

%N 210*n -/+ 17 ares both primes.

%H Vincenzo Librandi, <a href="/A075752/b075752.txt">Table of n, a(n) for n = 1..1000</a>

%e n=1: 210*1-17=193 and 210*1+17=227 are primes.

%t Select[Range[1, 300], PrimeQ[210 # - 17]&&PrimeQ[210 # + 17]&] (* _Vincenzo Librandi_, Oct 05 2013 *)

%o (PARI) isok(n) = isprime(210*n+17) && isprime(210*n-17); \\ _Michel Marcus_, Oct 03 2013

%o (Magma) [n: n in [1..350] | IsPrime(210*n-17) and IsPrime(210*n+17)]; // _Vincenzo Librandi_, Oct 05 2013

%K easy,nonn

%O 1,2

%A _Zak Seidov_, Oct 08 2002

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 16 05:35 EDT 2024. Contains 371697 sequences. (Running on oeis4.)