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%I #32 Sep 08 2022 08:45:00
%S 2,5,10,67,70,185,218,254,530,539,587,767,806,1142,1169,2098,3035,
%T 4310,8909,14150,15461,15778,15962,16711,17819,41915,78578,90047,
%U 274202,335351,430342,888782,1465658,1526518,2079167
%N Numbers k such that 279*2^k + 1 is prime.
%H Ray Ballinger and Wilfrid Keller, <a href="http://www.prothsearch.com/riesel1.html">List of primes k.2^n + 1 for k < 300</a>
%H Wilfrid Keller, <a href="http://www.prothsearch.com/riesel2.html">List of primes k*2^n - 1 for k < 300</a>
%H <a href="/index/Pri#riesel">Index entries for sequences of n such that k*2^n-1 (or k*2^n+1) is prime</a>
%t Select[Range[5*10^3], PrimeQ[279*2^# + 1] &] (* _G. C. Greubel_, May 24 2018 *)
%o (PARI) is(n)=ispseudoprime(279*2^n+1) \\ _Charles R Greathouse IV_, Jun 13 2017
%o (Magma) [n: n in [1..300] | IsPrime(279*2^n+1)]; // _G. C. Greubel_, May 24 2018
%K hard,nonn,more
%O 1,1
%A _N. J. A. Sloane_, Dec 29 1999
%E a(27)-a(34) from the Ray Ballinger and Wilfrid Keller link by _Robert Price_, Dec 20 2018
%E a(35) from _Jeppe Stig Nielsen_, May 30 2020