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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).
2
47, 107, 113, 233, 263, 307, 347, 353, 557, 563, 677, 743, 797, 953, 967, 977, 1087, 1097, 1103, 1217, 1223, 1277, 1307, 1427, 1483, 1523, 1553, 1597, 1733, 1823, 1877, 1913, 1973, 2027, 2207, 2237, 2243, 2267, 2333, 2417, 2447, 2663, 2687, 2753, 2777
OFFSET
1,1
EXAMPLE
47 is in the sequence because the period of the Fibonacci / Lucas numbers (mod 47) = 32, is not 2*(47+1) = 96.
PROG
(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
CROSSREFS
KEYWORD
nonn
AUTHOR
V. Raman, Sep 01 2012
EXTENSIONS
Definition corrected by V. Raman, Nov 22 2012
STATUS
approved