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Integers m such that A014448(m) == 5 (mod m).
1

%I #18 Jun 20 2020 02:12:15

%S 1,213,85887,974943,2463831,3952791,217643749,286354743,874273639,

%T 14029228621

%N Integers m such that A014448(m) == 5 (mod m).

%C Inspired by A335670.

%C All terms greater than 1 are odd and composite. - _Michel Marcus_, Jun 19 2020

%t Select[Range[10^5], Divisible[LucasL[3#] - 5, #] &] (* _Amiram Eldar_, Jun 19 2020 *)

%o (PARI) f(n) = my(w=quadgen(5)); (1+2*w)^n + (3-2*w)^n; \\ A014448

%o isok(m) = (m%2) && (m>1) && !isprime(m) && ((f(m) % m) == 5); \\ _Michel Marcus_, Jun 19 2020

%Y Cf. A014448, A335670, A335722.

%K nonn,more

%O 1,2

%A _Chai Wah Wu_, Jun 18 2020

%E a(7)-a(10) from _Giovanni Resta_, Jun 19 2020