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A160600
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Numbers n such that 3*(2n)^(2n)+1 is prime.
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0
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OFFSET
| 1,2
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COMMENTS
| 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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EXAMPLE
| 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
| (PARI) for(i=1, 9999, ispseudoprime(i^i*3+1)&print1(i/2, ", "))
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CROSSREFS
| Cf. A065798, A160360.
Sequence in context: A067799 A117702 A041343 * A140551 A064936 A041655
Adjacent sequences: A160597 A160598 A160599 * A160601 A160602 A160603
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KEYWORD
| hard,more,nonn
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AUTHOR
| M. F. Hasler (www.univ-ag.fr/~mhasler), Jul 10 2009
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