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%I #24 Jan 17 2019 10:08:17
%S 3,4,6,7,10,11,12,19,20,22,23,39,66,106,120,124,151,312,411,447,474,
%T 507,574,671,787,826,979,1690,1954,2047,3003,4323,4426,5903,6267,6846,
%U 14550,17470,21520,31711,36724,45291,45654,51778,55420,63439,68451,78423,109696,125128,130710,169836,192900,195028,383083,545716
%N Numbers k such that 153*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 Kosmaj, <a href="http://www.15k.org/riesellist.html">Riesel list 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[1000], PrimeQ[153*2^# - 1] & ] (* _Robert Price_, Dec 23 2018 *)
%o (PARI) is(n)=ispseudoprime(153*2^n-1) \\ _Charles R Greathouse IV_, Jun 13 2017
%K hard,nonn
%O 1,1
%A _N. J. A. Sloane_, Dec 29 1999
%E More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 02 2008
%E a(49)-a(56) from the Wilfrid Keller link by _Robert Price_, Dec 23 2018