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A096818
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Exponents n such that 2^n-13 is prime.
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13
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4, 5, 9, 13, 17, 57, 105, 137, 3217, 3229, 4233, 6097, 8757, 11457, 12073, 15425, 40117, 45357, 334809
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OFFSET
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1,1
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COMMENTS
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Except the first term 4, all terms are odd since for even n, 2^n-13 is divisible by 3.
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LINKS
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Table of n, a(n) for n=1..19.
Search for 2^n-13, PRP Top Records
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EXAMPLE
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n=5: 32-13=23 is prime.
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MATHEMATICA
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Select[Range[4, 20000], PrimeQ[2^#-13]&] (*From Vladimir Joseph Stephan Orlovsky, Feb 27 2011*)
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CROSSREFS
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Exponents for primes of 2^n-d form: A000043 (d=1), A050414 (d=3), A059608 (d=5), A059609 (d=7), A059610 (d=9), A096817 (d=11), A096818 (d=13), A059612 (d=15), A059611 (d=17), A096819 (d=19), A096820 (d=21).
Cf. A096502
Sequence in context: A006844 A022425 A116045 * A038099 A120740 A000285
Adjacent sequences: A096815 A096816 A096817 * A096819 A096820 A096821
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KEYWORD
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nonn,more
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AUTHOR
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Labos E. (labos(AT)ana.sote.hu), Jul 13 2004
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EXTENSIONS
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a(16) from Max Alekseyev, a(17)-a(18) from Henri Lifchitz, a(19) from Lelio R Paula, added by Max Alekseyev, Feb 09 2012
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STATUS
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approved
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