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Smaller of twin primes of the form 6*p(j)*p(k)-1, 6*p(j)*p(k)+1 where p(i)=i-th prime.
4

%I #12 Mar 29 2015 16:36:34

%S 59,149,197,227,347,461,521,569,857,1061,1229,1277,1289,1301,1481,

%T 1667,1721,1787,2129,3251,3257,3371,3389,3581,3929,4001,4217,4241,

%U 4337,4421,4517,4547,5009,5477,5501,5657,6689,6827,6869,7211,7457,7757,7877,8291

%N Smaller of twin primes of the form 6*p(j)*p(k)-1, 6*p(j)*p(k)+1 where p(i)=i-th prime.

%H Vincenzo Librandi, <a href="/A102168/b102168.txt">Table of n, a(n) for n = 1..500</a>

%e 6*2*5 = 60, {59, 61} twin primes.

%e 6*5*5 = 150, {149, 151} twin primes.

%e 6*3*11 = 198, {197, 199} twin primes.

%t t = Sort[ Flatten[ Table[6Prime[i]Prime[j], {i, 125}, {j, i}]]]; Take[ Select[t, PrimeQ[ # - 1] && PrimeQ[ # + 1] &] - 1, 44] (* _Robert G. Wilson v_, Mar 24 2005 *)

%t Take[Union[Select[6#-1&/@Times@@@Tuples[Prime[Range[200]],2],And@@ PrimeQ[ {#,#+2}]&]],50] (* _Harvey P. Dale_, May 22 2012 *)

%K nonn

%O 1,1

%A _Pierre CAMI_, Mar 15 2005

%E More terms from _Robert G. Wilson v_, Mar 24 2005