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 A290864 #44 Jun 17 2025 09:22:54 %S A290864 2,5,71,8419 %N A290864 Numbers k such that the k-th Fibonacci polynomial evaluated at k is prime. %C A290864 Numbers k such that A084844(k) = A117715(k,k) is prime. %C A290864 a(5) > 9200. - _Giovanni Resta_, Aug 13 2017 %C A290864 Except for a(1), all terms == 1 or 5 (mod 6). - _Robert Israel_, Aug 13 2017 %H A290864 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/FibonacciPolynomial.html">Fibonacci Polynomial</a> %H A290864 Wikipedia, <a href="https://en.wikipedia.org/wiki/Fibonacci_polynomials">Fibonacci polynomials</a> %e A290864 5 is in the sequence because A117715(5,5) = 701 is prime. %p A290864 select(t -> isprime(combinat:-fibonacci(t,t)), [2,seq(seq(6*i+j,j=[1,5]),i=0..100)]); # _Robert Israel_, Aug 13 2017 %t A290864 Select[Range[100], PrimeQ@ Fibonacci[#, #] &] (* _Giovanni Resta_, Aug 13 2017 *) %Y A290864 Cf. A000045, A011973, A084844, A117715, A162515, A168561. %K A290864 nonn,more,hard %O A290864 1,1 %A A290864 _Bobby Jacobs_, Aug 12 2017 %E A290864 a(4) from _Giovanni Resta_, Aug 13 2017