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A273871
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Primes p such that (4^(p-1)-1) == 0 mod ((p-1)^2+1).
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2
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OFFSET
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1,1
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COMMENTS
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The first 5 known Fermat primes from A019434 are in this sequence.
Conjecture 1: also primes p such that ((4^k)^(p-1)-1) == 0 mod ((p-1)^2+1) for all k >= 0.
Conjecture 2: supersequence of Fermat primes (A019434).
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LINKS
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EXAMPLE
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5 is a term because (4^(5-1)-1) == 0 mod ((5-1)^2+1); 255 == 0 mod 17.
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PROG
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(Magma) [n: n in [1..100000] | IsPrime(n) and (4^(n-1)-1) mod ((n-1)^2+1) eq 0]
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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STATUS
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approved
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