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Prime(k) such that the multiplicative order of prime(k) (mod prime(k+1)) = prime(k+1)-1.
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%I #18 Jul 05 2019 15:38:28

%S 2,3,5,7,11,19,43,59,61,67,79,83,101,103,127,131,139,151,163,179,181,

%T 197,223,251,257,269,271,307,317,337,347,353,367,379,419,421,439,443,

%U 461,463,467,487,499,523,541,563,577,587,593,607,643,659,691,709,727,733,739

%N Prime(k) such that the multiplicative order of prime(k) (mod prime(k+1)) = prime(k+1)-1.

%C Prime(k) is a term iff it is a primitive root of prime(k+1). These primes correspond to the records of A226295; if A226295(k) is such a record then prime(k) is a term in this sequence.

%H Robert Israel, <a href="/A308510/b308510.txt">Table of n, a(n) for n = 1..10000</a>

%e A226295(14) = 46 is a record, so prime(14)=43 is a term.

%t Select[Range[740], PrimeQ[#] && MultiplicativeOrder[#, p=NextPrime[#]] == p-1 &] (* _Amiram Eldar_, Jul 04 2019 *)

%o (PARI) isok(p) = isprime(p) && (q=nextprime(p+1)) && (znorder(Mod(p, q)) == q-1) \\ _Michel Marcus_, Jun 02 2019

%Y Cf. A226295.

%K nonn

%O 1,1

%A _David James Sycamore_, Jun 02 2019

%E More terms from _Michel Marcus_, Jun 02 2019