%I
%S 5,7,11,17,37,67,83,113,199,227,241,251,283,367,373,401,433,457,479,
%T 569,571,613,643,659,701,727,743,757,769,839,919,941,977,1019,1031,
%U 1049,1103,1109,1171,1187,1201,1249,1279,1367,1399,1423,1433,1471,1487,1493,1583,1601
%N Prime numbers p for which there is exactly one root x of x^3  x  1 in F_p and x is a primitive root mod p.
%C Gil, Weiner, & Zara prove that there is a unique complete Padovan sequence in F_p for each prime p in this sequence, which is generated by x.  _Charles R Greathouse IV_, Nov 26 2014
%H Juan B. Gil, Michael D. Weiner and Catalin Zara, <a href="http://www.fq.math.ca/Papers1/451/quartgil01_2007.pdf">Complete Padovan sequences in finite fields</a>, The Fibonacci Quarterly, Volume 45 Number 1, Feb 2007, pp. 6475, see p. 71.
%o (PARI) is(n)=if(!isprime(n), return(0)); my(f=factormod('x^3'x1,n)[,1]); f=select(t>poldegree(t)==1, f); #f==1 && znorder(polcoeff(f[1], 0))==n1 \\ _Charles R Greathouse IV_, Nov 26 2014
%Y Cf. A134573, A134574.
%K nonn
%O 1,1
%A _Gary W. Adamson_, Nov 01 2007
%E Corrected and extended by _Charles R Greathouse IV_, Nov 26 2014
%E New name from _Charles R Greathouse IV_, Nov 26 2014
