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A129963
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Primes of the form 4^n + n.
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0
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5, 67, 262153, 1073741839, 18889465931478580854821, 1496577676626844588240573268701473812127674924007509, 118571099379011784113736688648896417641748464297615937576404566024103044751294597
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| It is convenient, although not necessary, to let n be an odd number since n even => 4^n + n is even > 2. Conjecture: There is an infinite number of primes in this sequence.
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EXAMPLE
| For n = 3, 4^3+3=67 is prime.
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PROG
| (PARI) f(n) = for(x=1, n, y=2^x+x; if(isprime(y), print1(y", ")))
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CROSSREFS
| Sequence in context: A113064 A197776 A197606 * A115764 A003361 A099334
Adjacent sequences: A129960 A129961 A129962 * A129964 A129965 A129966
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KEYWORD
| nonn
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AUTHOR
| Cino Hilliard (hillcino368(AT)hotmail.com), Jun 10 2007, Aug 20 2007
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