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 A102168 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
 59, 149, 197, 227, 347, 461, 521, 569, 857, 1061, 1229, 1277, 1289, 1301, 1481, 1667, 1721, 1787, 2129, 3251, 3257, 3371, 3389, 3581, 3929, 4001, 4217, 4241, 4337, 4421, 4517, 4547, 5009, 5477, 5501, 5657, 6689, 6827, 6869, 7211, 7457, 7757, 7877, 8291 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Vincenzo Librandi, Table of n, a(n) for n = 1..500 EXAMPLE 6*2*5 = 60, {59, 61} twin primes. 6*5*5 = 150, {149, 151} twin primes. 6*3*11 = 198, {197, 199} twin primes. MATHEMATICA 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 *) Take[Union[Select[6#-1&/@Times@@@Tuples[Prime[Range[200]], 2], And@@ PrimeQ[ {#, #+2}]&]], 50] (* Harvey P. Dale, May 22 2012 *) CROSSREFS Sequence in context: A156796 A183348 A106756 * A142319 A140687 A118154 Adjacent sequences:  A102165 A102166 A102167 * A102169 A102170 A102171 KEYWORD nonn AUTHOR Pierre CAMI, Mar 15 2005 EXTENSIONS More terms from Robert G. Wilson v, Mar 24 2005 STATUS approved

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Last modified December 1 22:12 EST 2021. Contains 349435 sequences. (Running on oeis4.)