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%I #35 Dec 23 2024 13:33:45
%S 2,4,8,12,24,28,30,70,82,100,124,134,434,478,540,708,952,1052,1070,
%T 1528,1804,2568,2914,3712,16582,17342,23368,23942,35998,72174,142022,
%U 160658,177768,215140,238092,313540,461470,484500,868328,880188,1679938,1728894
%N Numbers k such that 193*2^k+1 is prime.
%H Jeppe Stig Nielsen, <a href="/A032473/b032473.txt">Table of n, a(n) for n = 1..48</a>
%H Ray Ballinger, <a href="http://www.prothsearch.com/index.html">Proth Search Page</a>
%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>
%p select(k->isprime(193*2^k+1),[$0..1000]); # _Muniru A Asiru_, Dec 18 2018
%t Select[Range[1000], PrimeQ[193*2^# + 1] & ] (* _Robert Price_, Dec 18 2018 *)
%o (PARI) is(n)=ispseudoprime(193*2^n+1) \\ _Charles R Greathouse IV_, Jun 13 2017
%K nonn,hard,changed
%O 1,1
%A _N. J. A. Sloane_.
%E a(31)-a(43) from the Ray Ballinger and Wilfrid Keller link by _Robert Price_, Dec 18 2018
%E Term moved from Data section to b-file, and more terms added to b-file, by _Jeppe Stig Nielsen_, Jan 19 2020