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A109994 Chen primes p such that their p + 2 counterpart is a Sarrus number (pseudoprime to base 2). 1

%I #8 Jun 28 2019 10:52:10

%S 2699,4679,10259,14489,18719,19949,31607,42797,49139,85487,90749,

%T 104651,129887,226799,294269,396269,422657,458987,481571,665279,

%U 710531,729059,1082399,1251947,1302449,1994687,2035151,2510567,2811269,3090089

%N Chen primes p such that their p + 2 counterpart is a Sarrus number (pseudoprime to base 2).

%C Conjecture: sequence is infinite.

%H Amiram Eldar, <a href="/A109994/b109994.txt">Table of n, a(n) for n = 1..10000</a>

%t Select[Range[10^5], PrimeQ[#] && PowerMod[2, (# + 1), # + 2] == 1 && PrimeNu[# + 2] == 2 &] (* _Amiram Eldar_, Jun 28 2019 *)

%Y Cf. A109611, A001567.

%K nonn

%O 1,1

%A _Jason Earls_, Sep 01 2005

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Last modified April 25 07:41 EDT 2024. Contains 371964 sequences. (Running on oeis4.)