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%I #38 Jan 18 2020 11:00:39
%S 4,8,13,14,20,31,38,70,80,86,110,125,140,170,179,230,338,365,374,517,
%T 860,944,1045,1270,1861,3623,4414,10448,27766,30836,34666,39826,55763,
%U 59260,70228,71590,76618,130388,189499,196303,202307,239773,240110,265954,422195
%N Numbers k such that 195*2^k+1 is prime.
%H Jeppe Stig Nielsen, <a href="/A032474/b032474.txt">Table of n, a(n) for n = 1..56</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(195*2^k+1),[$0..1000]); # _Muniru A Asiru_, Dec 18 2018
%t Select[Range[1000], PrimeQ[195*2^# + 1] & ] (* _Robert Price_, Dec 18 2018 *)
%o (PARI) is(n)=ispseudoprime(195*2^n+1) \\ _Charles R Greathouse IV_, Jun 13 2017
%K nonn,hard
%O 1,1
%A _N. J. A. Sloane_
%E a(38)-a(52) from the Ray Ballinger and Wilfrid Keller link by _Robert Price_, Dec 18 2018
%E Moved terms from Data section to b-file, and appended more terms to b-file, by _Jeppe Stig Nielsen_, Jan 18 2020
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