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.
%I A283653 #33 Sep 08 2022 08:46:19 %S A283653 0,2,3,4,5,17,29,31,53,59,101,277,647,1061,2381,2833,3613,3853,3929, %T A283653 5297,7417,90217,122219,173191,256199,336353,485977,591827,1059503 %N A283653 Numbers k such that 3^k + (-2)^k is prime. %C A283653 Numbers j such that both 3^j + (-2)^j and 3^j + (-4)^j are primes: 0, 3, 4, 17, 59, ... %C A283653 See Michael Somos comment in A082101. %C A283653 Probably this is just A057468 with 0,2,4 added, because we already know that if another even number belong to this sequence it must be greater than log_3(10^16000000) = about 3.3*10^7. This is because 3^n+2^n can be a prime with n>0 only if n is a power of 2. - _Giovanni Resta_, Mar 12 2017 %e A283653 4 is in this sequence because 3^4 + (-2)^4 = 97 is prime. %t A283653 Select[Range[0, 10000], PrimeQ[3^# + (-2)^#] &] (* _G. C. Greubel_, Jul 29 2018 *) %o A283653 (Magma) [n: n in [0..1000] | IsPrime(3^n+(-2)^n)]; %o A283653 (PARI) is(n)=isprime(3^n+(-2)^n) \\ _Charles R Greathouse IV_, Mar 16 2017 %Y A283653 Cf. A174326. Subsequence of A087451. Supersequence of A057468. %Y A283653 Cf. A082101. %K A283653 nonn,more %O A283653 1,2 %A A283653 _Juri-Stepan Gerasimov_, Mar 12 2017