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%I M1848 #33 Sep 08 2022 08:44:35
%S 2,8,32,54,114,414,1400,1850,2848,4874,7268,19290,337590,1183414
%N Numbers k such that k*3^k + 1 is prime.
%D H. Dubner, Generalized Cullen numbers, J. Rec. Math., 21 (No. 3, 1989), 190-191.
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H H. Dubner, <a href="/A005849/a005849.pdf">Generalized Cullen numbers</a>, J. Rec. Math., 21 (No. 3, 1989), 190-191. (Annotated scanned copy)
%H G. Loeh, <a href="http://guenter.loeh.name/gc/status.html">Generalized Cullen primes</a>
%t Select[Range[10000], PrimeQ[# 3^# + 1] &] (* _Vincenzo Librandi_, Dec 02 2015 *)
%o (Magma) [n: n in [0..420] | IsPrime(n*3^n+1)]; // _Vincenzo Librandi_, Dec 02 2015
%o (PARI) is(n)=ispseudoprime(n*3^n+1) \\ _Charles R Greathouse IV_, Feb 17 2017
%K nonn,hard
%O 1,1
%A _N. J. A. Sloane_
%E More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 05 2008
%E a(14) from Loeh link by _Ray Chandler_, Apr 10 2016
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