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%I M0976 N0365 #45 Feb 12 2021 17:46:42
%S 1,2,4,5,10,14,17,31,41,73,80,82,116,125,145,157,172,202,224,266,289,
%T 293,463,1004,1246,2066,2431,2705,4622,5270,7613,21727,21962,40742,
%U 41054,60622,83263,83669,91457,103940,104177,108124,115327,161453,172714,454681,568780,656264,712294,902474,1084010,1344313
%N Numbers k such that 15*2^k - 1 is prime.
%C The results were partially computed using the PrimeFormGW (PFGW) primality-testing program. - _Hugo Pfoertner_, Nov 14 2019
%D H. Riesel, "Prime numbers and computer methods for factorization", Progress in Mathematics, Vol. 57, Birkhauser, Boston, 1985, Chap. 4, see pp. 381-384.
%D N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%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>. <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>
%H H. Riesel, <a href="http://dx.doi.org/10.1090/S0025-5718-1969-0262163-1">Lucasian criteria for the primality of N=h.2^n-1</a>, Math. Comp., 23 (1969), 869-875.
%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>
%o (PARI) for(n=1, 10^10, if(ispseudoprime(15<<n-1), print1(n,", "))); \\ _Joerg Arndt_, Feb 23 2014
%Y Cf. A002258: 15*2^n+1 is prime.
%K hard,nonn
%O 1,2
%A _N. J. A. Sloane_, _Simon Plouffe_
%E More terms from _Hugo Pfoertner_, Jun 29 2004
%E More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 02 2008
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