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A136720 Prime quadruples: 2nd term.

%I A136720 #15 Oct 11 2019 15:54:55
%S A136720 7,13,103,193,823,1483,1873,2083,3253,3463,5653,9433,13003,15643,
%T A136720 15733,16063,18043,18913,19423,21013,22273,25303,31723,34843,43783,
%U A136720 51343,55333,62983,67213,69493,72223,77263,79693,81043,82723,88813,97843
%N A136720 Prime quadruples: 2nd term.
%C A136720 Primes p such that p-2, p+4, and p+6 are prime. Apart from the first term, a(n) = 13 (mod 30).
%H A136720 Robert Israel, <a href="/A136720/b136720.txt">Table of n, a(n) for n = 1..10000</a>
%F A136720 a(n) = A007530(n)+2 = A136721(n)-4 = A090258(n)-6. - _Robert Israel_, Oct 11 2019
%e A136720 The four terms in the first quadruple are 5,7,11,13 and in the 2nd 11,13,17,19. The four terms or members of each set must be simultaneously prime.
%p A136720 p2:= 0: p3:= 0: p4:= 0:
%p A136720 Res:= NULL: count:= 0:
%p A136720 while count < 100 do
%p A136720   p1:= p2; p2:= p3; p3:= p4;
%p A136720   p4:= nextprime(p4);
%p A136720   if [p2-p1, p3-p2, p4-p3] = [2,4,2] then
%p A136720      count:= count+1; Res:= Res, p2
%p A136720   fi
%p A136720 od:
%p A136720 Res; # _Robert Israel_, Oct 11 2019
%t A136720 lst={};Do[p0=Prime[n];If[PrimeQ[p2=p0+2], If[PrimeQ[p6=p0+6], If[PrimeQ[p8=p0+8], AppendTo[lst, p2]]]], {n, 12^4}];lst (* _Vladimir Joseph Stephan Orlovsky_, Aug 22 2008 *)
%Y A136720 Cf. A007530, A090258, A136721.
%K A136720 easy,nonn
%O A136720 1,1
%A A136720 _Enoch Haga_, Jan 18 2008
%E A136720 Edited by _Charles R Greathouse IV_, Oct 11 2009