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A191626
Integers n such that both 6n and 36n fall between pairs of twin primes, that is, 6n-1, 6n+1, 36n-1, and 36n+1 are prime.
4
2, 3, 5, 12, 23, 32, 45, 52, 58, 72, 107, 137, 138, 175, 182, 270, 278, 287, 325, 562, 577, 578, 597, 703, 747, 753, 872, 980, 1022, 1160, 1325, 1372, 1438, 1477, 1540, 1892, 1950, 2007, 2018, 2313, 2335, 2387, 2597, 2608, 2705, 2742, 2782, 3008
OFFSET
1,1
COMMENTS
Infinite under Dickson's conjecture. [Charles R Greathouse IV, Jul 24 2011]
LINKS
EXAMPLE
5 is in the list because 5*6=30, 5*36=180 and both fall between a pair of twin primes (29,31 and 179,181).
MATHEMATICA
Select[Range[3100], And@@PrimeQ[{6#+1, 6#-1, 36#+1, 36#-1}]&] (* Harvey P. Dale, Jul 27 2011 *)
CROSSREFS
Subsequence of A002822.
Cf. A014574.
Sequence in context: A183364 A124370 A003428 * A030041 A331811 A284910
KEYWORD
nonn
AUTHOR
Andrea Raffetti, Jul 11 2011
STATUS
approved