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%I #28 Sep 08 2022 08:44:39
%S 3,5,11,13,17,19,29,37,41,43,53,59,61,67,83,97,101,107,109,113,131,
%T 137,139,149,157,163,173,179,181,193,197,211,227,229,241,251,257,269,
%U 277,281,283,293,307,313,317,331,347,349,353,373,379,389,397,401,409,419
%N Primes p such that order of 2 mod p (=A007733(p)) is even.
%C Apart from the first term, identical to A091317. - _Charles R Greathouse IV_, Feb 13 2009
%D P. Moree, Appendix to V. Pless et al., Cyclic Self-Dual Z_4 Codes, Finite Fields Applic., vol. 3 pp. 48-69, 1997.
%H Klaus Brockhaus, <a href="/A014662/b014662.txt">Table of n, a(n) for n=1..1000</a>
%H C. Smyth, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL13/Smyth/smyth2.html">The terms in Lucas Sequences divisible by their indices</a>, JIS 13 (2010) #10.2.4.
%p select(t -> isprime(t) and numtheory:-order(2,t)::even, [2*i+1 $ i=1..1000]); # _Robert Israel_, Aug 12 2014
%t Select[Prime[Range[80]], EvenQ[MultiplicativeOrder[2, #/(2^IntegerExponent[ #, 2])]]&] (* _Jean-François Alcover_, Sep 02 2018 *)
%o (Magma) [ p: p in PrimesInInterval(3, 419) | IsEven(Modorder(2, p)) ] // _Klaus Brockhaus_, Dec 09 2008
%o (PARI) isok(p) = isprime(p) && !(znorder(Mod(2, p/2^valuation(p, 2))) % 2); \\ _Michel Marcus_, Sep 02 2018
%Y The prime terms of A296243.
%Y Cf. A091317.
%K nonn
%O 1,1
%A _N. J. A. Sloane_.
%E More terms from _Klaus Brockhaus_, Dec 09 2008
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