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A181669 Primes p of the form 6n-1 such that p-1 is a semiprime and p+2 is prime or prime squared. 6
5, 11, 23, 47, 59, 107, 167, 179, 227, 347, 359, 839, 1019, 1319, 1367, 1487, 1619, 2027, 2207, 2999, 3119, 3167, 3467, 4127, 4259, 4547, 4787, 4799, 5099, 5639, 5879, 6659, 6779, 6827, 7559, 8819, 10007, 10607, 11699, 12107, 12539, 14387, 14867, 15287, 15647 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Except term 7, same as A181602.

LINKS

Table of n, a(n) for n=1..45.

MATHEMATICA

Select[6*Range[3000]-1, PrimeQ[#]&&PrimeOmega[#-1]==2&&AnyTrue[ {#+2, Sqrt[ #+2]}, PrimeQ]&] (* Harvey P. Dale, Jul 01 2022 *)

CROSSREFS

Sequence in context: A337437 A107010 A175942 * A306662 A052940 A191304

Adjacent sequences: A181666 A181667 A181668 * A181670 A181671 A181672

KEYWORD

nonn

AUTHOR

Giovanni Teofilatto, Nov 18 2010

STATUS

approved

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Last modified February 5 03:48 EST 2023. Contains 360082 sequences. (Running on oeis4.)