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A335721
Integers m such that A014448(m) == 5 (mod m).
1
1, 213, 85887, 974943, 2463831, 3952791, 217643749, 286354743, 874273639, 14029228621
OFFSET
1,2
COMMENTS
Inspired by A335670.
All terms greater than 1 are odd and composite. - Michel Marcus, Jun 19 2020
MATHEMATICA
Select[Range[10^5], Divisible[LucasL[3#] - 5, #] &] (* Amiram Eldar, Jun 19 2020 *)
PROG
(PARI) f(n) = my(w=quadgen(5)); (1+2*w)^n + (3-2*w)^n; \\ A014448
isok(m) = (m%2) && (m>1) && !isprime(m) && ((f(m) % m) == 5); \\ Michel Marcus, Jun 19 2020
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Chai Wah Wu, Jun 18 2020
EXTENSIONS
a(7)-a(10) from Giovanni Resta, Jun 19 2020
STATUS
approved