%I #34 Sep 08 2022 08:46:24
%S 2,4,5,608,1221,60264,205965,994856,69709961,3140421767
%N Integers k such that the k-th prime divides the k-th Lucas number.
%p a:= 1:
%p b:= 2:
%p p:= 2:
%p Res:= NULL:
%p for n from 2 to 10^6 do
%p c:= a+b;
%p b:= a;
%p a:= c;
%p p:= nextprime(p);
%p if a mod p = 0 then
%p Res:= Res,n;
%p fi
%p od:
%p Res; # _Robert Israel_, Oct 30 2019
%o (Magma) [n: n in [1..100000] | IsZero(Lucas(n) mod NthPrime(n))];
%Y Cf. A000032, A000040.
%Y Cf. A075702 (analog with Fibonacci).
%K nonn,more
%O 1,1
%A _Juri-Stepan Gerasimov_, Oct 30 2019
%E a(8) from _Robert Israel_, Oct 30 2019
%E a(9)-a(10) from _Daniel Suteu_, Nov 07 2019
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