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.

A099381 Numbers n such that |Fibonacci(n) - prime(n)| is prime.

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%I A099381 #8 Dec 15 2017 17:36:47
%S A099381 2,3,6,8,9,12,15,24,33,48,225,525,948,1344,5169,30600,32520,32604,
%T A099381 72396
%N A099381 Numbers n such that |Fibonacci(n) - prime(n)| is prime.
%C A099381 Fibonacci(n) - prime(n) > 0 for n >= 8. All terms other than 2 and 8 (only two terms producing 2, the only even prime) are divisible by 3 (as Fibonacci(n) is even - and hence |Fibonacci(n) - prime(n)| > 1 and odd - iff n is divisible by 3).
%C A099381 Some of the larger entries may only correspond to probable primes.
%e A099381 9 is a term as Fibonacci(9) - prime(9) = 34 - 23 = 11, a prime.
%t A099381 fQ[n_] := PrimeQ[ Fibonacci[n] - Prime[n]]; Do[ If[ fQ[n], Print[n]], {n, 9, 10^4, 3}] (* _Robert G. Wilson v_, Nov 18 2004 *)
%o A099381 (PARI) print1(2,",",3,",",6,",",8,","); forstep(n=9,5169,3, if(isprime(fibonacci(n)-prime(n)), print1(n,",")))
%Y A099381 Cf. A050180 (Fibonacci(n) + prime(n) is prime).
%K A099381 nonn
%O A099381 1,1
%A A099381 _Rick L. Shepherd_, Nov 16 2004
%E A099381 4 more terms from _Jason Earls_, Nov 25 2007