%I M3247 N1310 #34 Sep 08 2022 08:44:30
%S 1,4,5,10,14,41,94,154,158,500,14140,19004,21928,44009,54629,57148,
%T 260653,281228,342280,519448,749938,930866
%N Numbers n such that 13*4^n + 1 is prime.
%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, <a href="http://www.prothsearch.com/index.html">Proth Search Page</a>
%H R. M. Robinson, <a href="https://doi.org/10.1090/S0002-9939-1958-0096614-7">A report on primes of the form k.2^n+1 and on factors of Fermat numbers</a>, Proc. Amer. Math. Soc., 9 (1958), 673-681.
%t Select[Range[2000],PrimeQ[13 4^#+1]&] (* _Harvey P. Dale_, Jan 22 2011 *)
%o (Magma) [ n: n in [1..800]|IsPrime(13*4^n+1)] // _Vincenzo Librandi_, Nov 21 2010
%o (PARI) for(n=1,10^5,if(ispseudoprime(13*4^n+1),print1(n,", "))); /* _Joerg Arndt_, Apr 07 2013 */
%Y See A032356 (n such that 13*2^n+1 is prime) for more terms.
%K nonn,more
%O 1,2
%A _N. J. A. Sloane_
%E Added more terms (from A032356), _Joerg Arndt_, Apr 07 2013