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Twin pack primes.
1

%I #9 Jan 21 2024 16:40:12

%S 3,5,7,11,13,17,19,101,103,107,109,137,139,149,151,179,181,191,193,

%T 197,199,419,421,431,433,809,811,821,823,827,829,1019,1021,1031,1033,

%U 1049,1051,1061,1063,1481,1483,1487,1489,1871,1873,1877

%N Twin pack primes.

%e A twin pack of primes contains 2 or more pairs of twin primes, between which pairs there are no other primes. 137,139,149,151 are in the sequence because they are consecutive primes which belong to more than 1 twin pair. 29,31 are not because both the preceding prime 23 and the next prime 37 are non-twins.

%t Join[{3},Flatten[Select[Partition[Prime[Range[300]],4,1],#[[2]]-#[[1]] == #[[4]]-#[[3]] == 2&]]// Union] (* _Harvey P. Dale_, Jan 13 2017 *)

%Y Cf. A001097, A069457.

%K nonn

%O 1,1

%A _Neil Fernandez_, Mar 23 2002