Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #26 Nov 19 2023 08:26:20
%S 6,8,12,16,18,20,22,24,32,36,42,44,96,104,152,174,198,336,414,444,468,
%T 488,664,808,848,3632,4062,5586,5904,6348,8628,9224,9916,13136,15966,
%U 17120,17568,17652,20560,31572,33644,104098,115842,130572,164110,189414,205110,406758
%N Numbers k such that 2^k - 17 is prime.
%C All terms are even since for odd k, 2^k - 17 is divisible by 3.
%H Henri Lifchitz and Renaud Lifchitz, <a href="http://www.primenumbers.net/prptop/searchform.php?form=2%5En-17">Search for 2^n-17</a>, PRP Top Records.
%e 444 is present because 2^444 - 17 is prime.
%t Select[Range[5,20000],PrimeQ[2^#-17]&] (* _Vladimir Joseph Stephan Orlovsky_, Feb 27 2011 *)
%o (PARI) is(n)=isprime(2^n-17) \\ _Charles R Greathouse IV_, Feb 17 2017
%Y Cf. A096502.
%Y 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), A096817 (d=11), A096818 (d=13), A059612 (d=15), this sequence (d=17), A096819 (d=19), A096820 (d=21), A057220 (d=23), A356826 (d=29).
%K nonn
%O 1,1
%A _Andrey V. Kulsha_, Feb 05 2001
%E a(34)-a(40) from Max Alekseyev, a(41) from Paul Underwood, a(42)-a(44) from Gary Barnes, a(45)-a(47) from Lelio R Paula, added by _Max Alekseyev_, Feb 09 2012
%E a(48) by Lelio R. Paula, added by _Robert Price_, Dec 06 2013