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Primes p such that Jacobi(p,91) = 1.
3

%I #16 Sep 08 2022 08:45:57

%S 5,19,23,29,31,41,43,47,53,59,73,79,83,89,97,107,113,127,167,179,191,

%T 211,223,227,229,233,241,263,271,277,293,307,337,347,349,353,373,383,

%U 389,397,409,443,461,479,491,509,547,569,571,577,587,593,599,619,641

%N Primes p such that Jacobi(p,91) = 1.

%C Originally incorrectly named "Primes that are squares mod 91", which is sequence A106989, and a subsequence of this one, because these primes have (p|7) = (p|13) = 1. The present sequence includes also primes with (p|7) = (p|13) = -1. - _David Broadhurst_ and _M. F. Hasler_, Jan 15 2016

%H Vincenzo Librandi, <a href="/A191054/b191054.txt">Table of n, a(n) for n = 1..1000</a>

%t Select[Prime[Range[200]], JacobiSymbol[#,91]==1&]

%o (Magma) [p: p in PrimesUpTo(641) | JacobiSymbol(p, 91) eq 1]; // _Vincenzo Librandi_, Sep 10 2012

%o (PARI) is(p)=kronecker(p,91)==1&&isprime(p) \\ _M. F. Hasler_, Jan 15 2016

%K nonn,easy

%O 1,1

%A _T. D. Noe_, May 25 2011

%E Definition corrected, following a suggestion from _David Broadhurst_, by _M. F. Hasler_, Jan 15 2016