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A129962
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Primes of the form 2^n + n.
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1
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3, 11, 37, 521, 32783, 549755813927, 37778931862957161709643, 2417851639229258349412433, 618970019642690137449562201, 266998379490113760299377713271194014325338065294581596243380200977777465722580068752870260867389
(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 => 2^n + n is even > 2. Conjecture: There is an infinite number of primes in this sequence. If n is prime we have A057664.
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EXAMPLE
| for n = 3, 2^3+3=11 prime and the second entry.
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MATHEMATICA
| Select[Table[2^n+n, {n, 600}], PrimeQ[#]&] (*From Vladimir Joseph Stephan Orlovsky, Feb 18 2011*)
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PROG
| (PARI) f(n) = forstep(x=1, n, 2, y=2^x+x; if(isprime(y), print1(y", ")))
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CROSSREFS
| Cf. A052007 (values of n), A057664, A081296.
Sequence in context: A047102 A109000 A183511 * A026361 A006189 A092201
Adjacent sequences: A129959 A129960 A129961 * A129963 A129964 A129965
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KEYWORD
| nonn
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AUTHOR
| Cino Hilliard (hillcino368(AT)hotmail.com), Jun 10 2007
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