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Numbers k such that 3^k + 100 is prime.
1

%I #18 Oct 24 2024 12:32:56

%S 0,1,2,3,4,6,7,8,10,18,24,26,54,63,90,91,97,156,172,230,262,344,406,

%T 435,556,630,644,667,978,1178,1189,1645,1768,2362,2578,2701,2724,2804,

%U 2928,3082,3202,3276,4429,12036,15280,19212,19642,21250,25224,37674,52946,66972

%N Numbers k such that 3^k + 100 is prime.

%t Select[Range[5000], PrimeQ[3^# + 100] &]

%o (PARI) is(n)=ispseudoprime(3^n+100) \\ _Charles R Greathouse IV_, Jun 13 2017

%Y Cf. A176929 (associated primes).

%K nonn

%O 1,3

%A _Vincenzo Librandi_, Dec 01 2012

%E a(44)-a(50) from _Michael S. Branicky_, Jul 14 2023

%E a(1)=0 inserted and a(51)-a(52) from _Michael S. Branicky_, Oct 24 2024