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A216067 Prime numbers p such that p is odd and is congruent to 2 (mod 5) or 3 (mod 5), but the period of the irreducible polynomial x^2-x-1 in GF(p^2) is not 2*(p+1).

%I A216067 #11 Aug 19 2016 00:28:00
%S A216067 47,107,113,233,263,307,347,353,557,563,677,743,797,953,967,977,1087,
%T A216067 1097,1103,1217,1223,1277,1307,1427,1483,1523,1553,1597,1733,1823,
%U A216067 1877,1913,1973,2027,2207,2237,2243,2267,2333,2417,2447,2663,2687,2753,2777
%N A216067 Prime numbers p such that p is odd and is congruent to 2 (mod 5) or 3 (mod 5), but the period of the irreducible polynomial x^2-x-1 in GF(p^2) is not 2*(p+1).
%H A216067 V. Raman, <a href="/A216067/b216067.txt">Table of n, a(n) for n = 1..10000</a>
%e A216067 47 is in the sequence because the period of the Fibonacci / Lucas numbers (mod 47) = 32, is not 2*(47+1) = 96.
%o A216067 (PARI) forprime(p=3,3000,if(p%5==2||p%5==3,a=1;b=0;c=1;while(a!=0||b!=1,c++;d=a;a=b;a=(a+d)%p;b=d%p);if(c!=(2*(p+1)),print1(p",")))) \\ _V. Raman_, Nov 22 2012
%Y A216067 Cf. A001175, A060305, A071776.
%Y A216067 Cf. A071774.
%K A216067 nonn
%O A216067 1,1
%A A216067 _V. Raman_, Sep 01 2012
%E A216067 Definition corrected by _V. Raman_, Nov 22 2012