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A288794
Numbers k such that Lucas(k) + prime(k) is a prime.
1
1, 6, 12, 18, 54, 75, 354, 10158, 23280, 33726, 38226, 70749, 244779, 308604
OFFSET
1,2
COMMENTS
a(15) > 500000.
EXAMPLE
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.
MATHEMATICA
Select[Range[1000], PrimeQ[LucasL[#] + Prime[#]] &]
PROG
(Magma) [n: n in [1..950] | IsPrime(Lucas(n)+NthPrime(n))];
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Vincenzo Librandi, Jun 16 2017
EXTENSIONS
a(8)-a(12) from Robert Price, Oct 26 2017
a(13)-a(14) from Robert Price, Dec 16 2017
STATUS
approved