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%I #9 Aug 11 2024 04:58:26
%S 3,244672067,14551915378461487103639747,
%T 3552713678880267372432493847753987,
%U 211758236813575107295480170109084902352995775163267
%N Primes of form 1 + 3^k + 5^k.
%H Amiram Eldar, <a href="/A081508/b081508.txt">Table of n, a(n) for n = 1..6</a>
%F a(n) = A074507(A076515(n)). - _Amiram Eldar_, Aug 11 2024
%t Do[s=1^w+3^w+5^w; If[IntegerQ[w/100], Print[{w}]]; If[PrimeQ[s], Print[{w, s}]], {w, 0, 1000}]
%o (PARI) lista(kmax) = {my(p); for(k = 0, kmax, p = 1 + 3^k + 5^k; if(isprime(p), print1(p, ", ")));} \\ _Amiram Eldar_, Aug 11 2024
%Y Cf. A074507, A076515, A277122.
%K nonn
%O 1,1
%A _Labos Elemer_, Apr 15 2003