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A160600
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Numbers n such that 3*(2n)^(2n)+1 is prime.
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4
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OFFSET
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1,2
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COMMENTS
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This corresponds to the numbers such that 3m^m+1 is prime, but these must all be even, m=2n, and therefore it is more natural to record the sequence of n=m/2.
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LINKS
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EXAMPLE
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a(1) = 1, because 2^2*3+1 = 13 is the smallest prime of this form.
a(2) = 2, because 4^4*3+1 = 769 is the next smallest prime of this form. a(3) = 3, because 6^6*3+1 = 139969 is again a prime.
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PROG
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(PARI) for(i=1, 9999, ispseudoprime(i^i*3+1)&print1(i/2, ", "))
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CROSSREFS
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KEYWORD
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hard,more,nonn
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AUTHOR
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STATUS
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approved
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