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Twin primes belonging to packs of three or more twin pairs.
1

%I #10 Jan 12 2015 08:37:00

%S 3,5,7,11,13,17,19,179,181,191,193,197,199,809,811,821,823,827,829,

%T 3359,3361,3371,3373,3389,3391,4217,4219,4229,4231,4241,4243,6761,

%U 6763,6779,6781,6791,6793,9419,9421,9431,9433,9437,9439,9461,9463,18041

%N Twin primes belonging to packs of three or more twin pairs.

%e A twin pack of primes contains 2 or more pairs of twin primes, between which pairs there are no other primes. 179, 181, 191, 193, 197, 199 are in the sequence because they are consecutive primes which belong to more than 2 twin pairs. 137, 139, 149, 151 are not because they belong to a pack of only 2 pairs.

%t lst={3}; d=2; Do[p0=Prime[n+0]; p1=Prime[n+1]; p2=Prime[n+2]; p3=Prime[n+3]; p4=Prime[n+4]; p5=Prime[n+5]; d1=p1-p0; d2=p3-p2; d3=p5-p4; If[d1==d&&d2==d&&d3==d, AppendTo[lst, p0]; AppendTo[lst, p1]; AppendTo[lst, p2]; AppendTo[lst, p3]; AppendTo[lst, p4]; AppendTo[lst, p5]], {n, 10^4}]; Union[lst] (* _Vladimir Joseph Stephan Orlovsky_, Aug 08 2008 *)

%Y Cf. A001097, A069458.

%K nonn

%O 1,1

%A _Neil Fernandez_, Mar 24 2002