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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Infinite under Dickson's conjecture. [Charles R Greathouse IV, Jul 24 2011]

LINKS

Andrea Raffetti, Table of n, a(n) for n = 1..999

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

Adjacent sequences:  A191623 A191624 A191625 * A191627 A191628 A191629

KEYWORD

nonn

AUTHOR

Andrea Raffetti, Jul 11 2011

STATUS

approved

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Last modified October 26 02:14 EDT 2021. Contains 348256 sequences. (Running on oeis4.)