cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A268065 Integers k such that 2^k + 3^k + 5^k + k is prime.

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%I A268065 #25 Dec 01 2024 15:53:49
%S A268065 0,1,3,7,19,33,1363,6663
%N A268065 Integers k such that 2^k + 3^k + 5^k + k is prime.
%C A268065 a(8), if it exists, is greater than 30000. - _Vaclav Kotesovec_, Jan 26 2016
%C A268065 a(8), if it exists, is greater than 100000. - _Michael S. Branicky_, Dec 01 2024
%e A268065 k=3: 2^3+3^3+5^3+3 = 163.
%t A268065 Select[Range[0, 2000], PrimeQ[2^# + 3^# + 5^# + #] &] (* _Vaclav Kotesovec_, Jan 25 2016 *)
%o A268065 (PARI) lista(nn) = for(n=0, nn, if(ispseudoprime(2^n + 3^n + 5^n + n), print1(n, ", "))); \\ _Altug Alkan_, Jan 25 2016
%Y A268065 Cf. A076515, A268067.
%K A268065 nonn,more
%O A268065 1,3
%A A268065 _Emre APARI_, Jan 25 2016
%E A268065 a(7) from _Vaclav Kotesovec_, Jan 25 2016