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A217090
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Optimus primes.
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3
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5, 7, 11, 13, 17, 19, 29, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 127, 131, 139, 149, 151, 157, 163, 167, 173, 179, 181, 193, 197, 199, 211, 223, 227, 229, 233, 241, 251, 257, 263, 269, 271, 281, 283, 293, 307, 311, 313
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OFFSET
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1,1
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COMMENTS
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An odd prime p is an optimus prime if (1 + sqrt(Legendre(-1, p)*p))^p - 1 = a + b*sqrt(Legendre(-1, p)*p), where gcd(a, b) = p.
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LINKS
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PROG
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(PARI) is(p)=if(p<3 || !isprime(p), return(0)); my(t=(2*quadgen(kronecker(-1, p)*p))^p); gcd(imag(t), real(t)-1)==p \\ Charles R Greathouse IV, Sep 26 2012
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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