A099381
Numbers n such that |Fibonacci(n) - prime(n)| is prime.
Original entry on oeis.org
2, 3, 6, 8, 9, 12, 15, 24, 33, 48, 225, 525, 948, 1344, 5169, 30600, 32520, 32604, 72396
Offset: 1
9 is a term as Fibonacci(9) - prime(9) = 34 - 23 = 11, a prime.
Cf.
A050180 (Fibonacci(n) + prime(n) is prime).
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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 *)
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print1(2,",",3,",",6,",",8,","); forstep(n=9,5169,3, if(isprime(fibonacci(n)-prime(n)), print1(n,",")))
A288794
Numbers k such that Lucas(k) + prime(k) is a prime.
Original entry on oeis.org
1, 6, 12, 18, 54, 75, 354, 10158, 23280, 33726, 38226, 70749, 244779, 308604
Offset: 1
a(1) = 1 because Lucas(1)=1, prime(1)=2 and 1+2=3 is a prime.
a(2) = 6 because Lucas(6)=18, prime(6)=13 and 18+13=31 is a prime.
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[n: n in [1..950] | IsPrime(Lucas(n)+NthPrime(n))];
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Select[Range[1000], PrimeQ[LucasL[#] + Prime[#]] &]
A297623
Numbers k such that Lucas(k) - prime(k) is a prime.
Original entry on oeis.org
6, 9, 18, 33, 51, 54, 57, 189, 6948, 28617, 162864, 173682, 216870, 496533
Offset: 1
a(1) = 6 because Lucas(6)=18, prime(6)=13 and 18-13=5 is a prime.
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[n: n in [1..5000] | IsPrime(Lucas(n)-NthPrime(n))];
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Select[Range[10000], PrimeQ[LucasL[#] - Prime[#]]&]
Showing 1-3 of 3 results.
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