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.

A155011 Sophie Germain Fibonacci prime numbers.

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%I A155011 #23 Nov 08 2017 07:42:24
%S A155011 2,3,5,89,233,
%T A155011 10597999265301490732599643671505003412515860435409421932560009680142974347195483140293254396195769876129909
%N A155011 Sophie Germain Fibonacci prime numbers.
%C A155011 2*2+1=5, 2*3+1=7, 2*5+1=11, ...
%C A155011 No additional terms up through Fibonacci(10000). - _Harvey P. Dale_, Nov 26 2013
%C A155011 No additional terms up through Fibonacci(50000). - _Chai Wah Wu_, Nov 04 2015
%F A155011 a(n) = (A263880(n) - 1)/2. - _Jonathan Sondow_, Nov 04 2015
%t A155011 a={};Do[f=Fibonacci[n];If[PrimeQ[f],If[PrimeQ[2*f+1],AppendTo[a,f]]],{n,3*6!}];a
%t A155011   Select[Fibonacci[Range[2000]],And@@PrimeQ[{#,2#+1}]&] (* _Harvey P. Dale_, Nov 26 2013 *)
%o A155011 (Python)
%o A155011 from gmpy2 import is_prime
%o A155011 A155011_list = []
%o A155011 a, b, a2, b2 = 0, 1, 1, 3
%o A155011 for _ in range(10**6):
%o A155011     if is_prime(b) and is_prime(b2):
%o A155011         A155011_list.append(b)
%o A155011     a, b, a2, b2 = b, a+b, b2, a2+b2-1 # _Chai Wah Wu_, Nov 04 2015
%Y A155011 Cf. A005478, A000045, A005384, A263880.
%K A155011 nonn
%O A155011 1,1
%A A155011 _Vladimir Joseph Stephan Orlovsky_, Jan 18 2009