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A117847 Numbers n such that A060256(n)*p(n)#-1 is a Sophie Germain prime. 0
10, 15, 24, 35, 37, 79, 340 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

This sequence gives first of twin primes which are also Sophie Germain primes

LINKS

Table of n, a(n) for n=1..7.

EXAMPLE

16*(29#)-1 is the first of twin primes, 16=A060256(10)

2*(16*(29#)-1)+1 is prime so 16*(29#)-1 is a Sophie Germain prime

CROSSREFS

Cf. A060256.

Sequence in context: A207637 A171444 A227371 * A057990 A272779 A173477

Adjacent sequences:  A117844 A117845 A117846 * A117848 A117849 A117850

KEYWORD

hard,more,nonn

AUTHOR

Pierre CAMI, May 01 2006

STATUS

approved

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Last modified December 7 05:14 EST 2019. Contains 329839 sequences. (Running on oeis4.)