# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a263468 Showing 1-1 of 1 %I A263468 #10 Nov 05 2015 08:16:53 %S A263468 5,13,89,233,28657,2971215073 %N A263468 Fibonacci primes equal to a sum of squares of two Fibonacci numbers at least one of which is also prime. %C A263468 Same as Fibonacci numbers F(2k+1) such that at least two of the numbers F(2k+1), F(k), F(k+1) are prime (because F(2k+1) = F(k)^2 + F(k+1)^2 and F(a*b)= F(a) * F(b))). Thus the two squares are of consecutive Fibonacci numbers. %C A263468 No other terms up to F(2904353). %C A263468 The corresponding Fibonacci indices are in A263467. %C A263468 Subsequence of A002144 and A002313. %H A263468 Wikipedia, Fibonacci number %H A263468 Wikipedia, Fibonacci prime %F A263468 a(n) = A000045(A263467(n)). %e A263468 F(47) = 2971215073 = 28657^2 + 46368^2 = F(23)^2 + F(24)^2 and 2971215073 and 28657 are prime, so 2971215073 is a member. %Y A263468 Cf. A000045, A001605, A002144, A002313, A005478, A263467. %K A263468 nonn,more %O A263468 1,1 %A A263468 _Jonathan Sondow_, Nov 04 2015 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE