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%I #34 Jul 26 2024 12:33:43
%S 1,2,3,4,5,6,8,10,11,12,19,27,28,32,36,48,56,61,131,170,251,750,771,
%T 779,790,874,1176,1728,2604,3541,5394,6203,9230,14666,15680,26712,
%U 45840,46019,56220
%N Numbers k such that (2^k + 3)^2 - 8 is prime.
%H Daniel Shanks, <a href="https://doi.org/10.1090/S0025-5718-1971-0297737-4">Gauss's ternary form reduction and the 2-Sylow subgroup</a>, Math. Comp. 25 (1971), 837-853.
%o (PARI) for(n=1,10^6,if(isprime((2^n+3)^2-8),print1(n,", "))); /* _Joerg Arndt_, Apr 25 2011 */
%Y Cf. A188129, A188661, A188937.
%K nonn,more
%O 1,2
%A _N. J. A. Sloane_, Apr 14 2011
%E a(22)-a(30) from _Joerg Arndt_, Apr 25 2011
%E a(31)-a(33) from _Vincenzo Librandi_, May 13 2011
%E a(36) from _Charles R Greathouse IV_, Oct 10 2011
%E a(37)-a(39) from _Charles R Greathouse IV_, Oct 11 2011
%E a(34)-a(35) inserted by _Michael S. Branicky_, Jul 25 2024