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!)
A340225 Primes p such that 2*p+q and 2*p+r are prime, where q and r are the next two primes after p. 2

%I #8 Jan 01 2021 18:10:00

%S 3,19,241,439,577,743,787,983,1549,1637,1699,1879,2273,2843,3929,4157,

%T 4201,4583,5669,5791,6301,6659,7559,11887,12163,12517,12889,13007,

%U 13049,13219,13759,13879,14149,15139,18443,18539,18959,19793,23431,23629,23993,24419,25127,26737,27407,27739,27799,28409

%N Primes p such that 2*p+q and 2*p+r are prime, where q and r are the next two primes after p.

%H Robert Israel, <a href="/A340225/b340225.txt">Table of n, a(n) for n = 1..10000</a>

%e a(3) = 241 is a term because it is prime, the next two primes are 251 and 257, and 2*241+251 = 733 and 2*241+257 = 739 are prime.

%p R:= NULL: count:= 0:

%p q:= 2: r:= 3:

%p while count < 100 do

%p p:= q; q:= r; r:= nextprime(r);

%p if isprime(2*p+q) and isprime(2*p+r) then

%p count:= count+1; R:= R, p;

%p fi

%p od:

%p R;

%Y Cf. A340210.

%K nonn

%O 1,1

%A _J. M. Bergot_ and _Robert Israel_, Jan 01 2021

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 March 28 14:21 EDT 2024. Contains 371254 sequences. (Running on oeis4.)