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%I #15 Aug 16 2024 17:41:50
%S 11,31,89,761,2251,6689,59561,14365291,10461401779,282437925089,
%T 150094669656737489,239299329512092506300739,
%U 2153693964201457673153371,107752636643058216783050887908587014548761
%N Primes of the form 2^(k-1) + 3^k.
%H Harvey P. Dale, <a href="/A082102/b082102.txt">Table of n, a(n) for n = 1..30</a>
%F a(n) = 2^(A082103(n)-1) + 3^A082103(n). - _Amiram Eldar_, Aug 16 2024
%e 89 = 2^3 + 3^4.
%t Do[s=2^(w-1)+3^w; If[PrimeQ[s], Print[s]], {w, 1, 2000}]
%t Select[Table[2^(n-1)+3^n,{n,100}],PrimeQ] (* _Harvey P. Dale_, Feb 09 2016 *)
%o (PARI) lista(kmax) = {my(p); for(k = 1, kmax, p = 2^(k-1) + 3^k; if(isprime(p), print1(p, ", ")));} \\ _Amiram Eldar_, Aug 16 2024
%Y Cf. A082101, A082103.
%K nonn
%O 1,1
%A _Labos Elemer_, Apr 14 2003