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!)
A175914 Primes p such that p+2*q is prime, where q is the prime after p. 6

%I #28 Sep 08 2022 08:45:52

%S 3,5,7,11,13,41,43,59,89,101,103,113,127,179,181,191,193,223,241,269,

%T 277,293,307,311,313,337,359,421,431,479,491,521,599,613,631,673,773,

%U 787,821,823,863,881,883,907,911,919,929,937,953,967,1019,1021,1039,1061,1109,1151,1171

%N Primes p such that p+2*q is prime, where q is the prime after p.

%C A174915 gives lesser of twin primes in this sequence.

%C Values of p+2*q are in A094105. [_Zak Seidov_, Sep 07 2012]

%H Zak Seidov, <a href="/A175914/b175914.txt">Table of n, a(n) for n = 1..1000</a>

%e 3 and 5 are consecutive primes, and 3+2*5 = 13 is prime. Hence 3 is in the sequence.

%e 59 and 61 are consecutive primes, and 59+2*61 = 181 is prime. Hence 59 is in the sequence.

%t p = 3; Reap[Do[q = NextPrime[p]; If[PrimeQ[p + 2 q], Sow[p]]; p = q, {10^3}]][[2, 1]] (* _Zak Seidov_, Oct 14 2012 *)

%o (Magma) [p: p in PrimesUpTo(1200) | IsPrime(p+2*NextPrime(p))]; // _Klaus Brockhaus_, Dec 06 2010

%Y Cf. A094105, A114262, A174915, A001359.

%K nonn

%O 1,1

%A _Zak Seidov_, Dec 05 2010

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 24 00:30 EDT 2024. Contains 371917 sequences. (Running on oeis4.)