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.

A328381 Lesser of twin primes pair p, such that F(p) and F(p+2) have the same number of prime factors, where F(n) is the n-th Fibonacci number.

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%I A328381 #4 Oct 14 2019 21:13:32
%S A328381 3,5,11,59,71,107,179,191,311,431,569,599,827,881
%N A328381 Lesser of twin primes pair p, such that F(p) and F(p+2) have the same number of prime factors, where F(n) is the n-th Fibonacci number.
%C A328381 No more terms below 1427.
%C A328381 The corresponding number of prime factors is 1, 1, 1, 2, 2, 2, 3, 2, 4, 1, 1, 2, 5, ...
%C A328381 Assuming that Fibonacci numbers with prime index are always squarefree, the distinction between number of prime factors with multiplicity (A001222) and number of distinct prime factors (A001221) is inessential.
%e A328381 3 is in the sequence since 3 and 5 are twin primes, and F(3) = 2 and F(5) = 5 are both primes, thus having the same number of prime factors.
%e A328381 71 is in the sequence since 71 and 73 are twin primes, and F(71) and F(73) both have 2 prime factors.
%t A328381 s={}; Do[If[PrimeQ[n] && PrimeQ[n+2] && PrimeOmega[Fibonacci[n]] == PrimeOmega[ Fibonacci[n+2]], AppendTo[s, n]], {n, 1, 200}]; s
%Y A328381 Cf. A000045, A001359, A001605, A005478, A022307, A038575, A319908.
%Y A328381 Supersequence of A281087.
%K A328381 nonn,more
%O A328381 1,1
%A A328381 _Amiram Eldar_, Oct 14 2019