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A096817
Numbers k such that 2^k - 11 is prime.
14
4, 6, 10, 18, 42, 78, 94, 114, 190, 322, 546, 3894, 10318, 11650, 12474, 20994, 61810, 103882, 296010, 636930, 653638, 926766
OFFSET
1,1
COMMENTS
All terms are even since for odd k, 2^k - 11 is divisible by 3.
LINKS
Henri Lifchitz and Renaud Lifchitz, Search for 2^n-11, PRP Top Records.
EXAMPLE
k = 6: 64 - 11 = 53 is prime.
MATHEMATICA
Select[Range[4, 20000], PrimeQ[2^#-11]&] (* Vladimir Joseph Stephan Orlovsky, Feb 26 2011*)
CROSSREFS
Cf. A096502.
Cf. Sequences of numbers k such that 2^k - d is prime: A000043 (d=1), A050414 (d=3), A059608 (d=5), A059609 (d=7), A059610 (d=9), this sequence (d=11), A096818 (d=13), A059612 (d=15), A059611 (d=17), A096819 (d=19), A096820 (d=21), A057220 (d=23), A356826 (d=29).
Sequence in context: A027976 A108900 A076995 * A220033 A277455 A320124
KEYWORD
nonn,more
AUTHOR
Labos Elemer, Jul 13 2004
EXTENSIONS
a(13)-a(16) from Max Alekseyev, a(17)-a(18) from Henri Lifchitz, added by Max Alekseyev, Feb 09 2012
a(19) from Lelio R Paula, added by Max Alekseyev, Oct 24 2013
a(20)-a(22) from Stefano Morozzi, added by Elmo R. Oliveira, Nov 16 2023
STATUS
approved