A152469 Second smallest of three consecutive primes whose sum is a prime.

7, 11, 13, 19, 23, 29, 31, 37, 43, 59, 67, 71, 73, 83, 89, 103, 113, 149, 151, 163, 167, 199, 223, 233, 277, 283, 293, 307, 313, 347, 349, 353, 383, 397, 409, 419, 433, 457, 461, 467, 479, 499, 503, 521, 557, 619, 643, 659, 661, 673, 709, 727, 751, 757, 761

Offset: 1

Author

Vladimir Joseph Stephan Orlovsky, Dec 05 2008

Keywords

• nonn

Links

• Harvey P. Dale, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A073681, A072225, A152468, A152470.

Programs

Maple

t0:=[];
t1:=[];
t2:=[];
t3:=[];
for i from 1 to 1000 do
t3:=ithprime(i)+ithprime(i+1)+ithprime(i+2);
if isprime(t3) then
t0:=[op(t0),i];
t1:=[op(t1),ithprime(i)];
t2:=[op(t2),ithprime(i+1)];
t3:=[op(t2),ithprime(i+2)];
fi;
od:
t2;

Mathematica

lst={};Do[p0=Prime[n];p1=Prime[n+1];p2=Prime[n+2];If[PrimeQ[p0+p1+p2],AppendTo[lst,p1]],{n,6!}];lst
Select[Partition[Prime[Range[200]],3,1],PrimeQ[Total[#]]&][[All,2]] (* Harvey P. Dale, May 08 2021 *)