OFFSET
1,1
COMMENTS
If n is a prime, not 5, then Fibonacci(n) == Legendre(n,5) (mod n) (see for example G. H. Hardy and E. M. Wright, Theory of Numbers).
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
Masataka Yorinaga, On a congruencial property of Fibonacci numbers (numerical experiments), Math. J. Okayama Univ. 19 (1976/77), no. 1, 5-10.
Masataka Yorinaga, On a congruencial property of Fibonacci numbers (considerations and remarks), Math. J. Okayama Univ. 19 (1976/77), no. 1, 11-17.
MATHEMATICA
Select[ Range[ 2, 5000 ], ! PrimeQ[ # ] && Mod[ Fibonacci[ # ] - JacobiSymbol[ #, 5 ], # ] == 0 & ]
PROG
(PARI) N=10^4; for(n=2, N, if(Mod((fibonacci(n)), n)==kronecker(n, 5) && !isprime(n), print1(n, ", ")));
CROSSREFS
KEYWORD
nonn
AUTHOR
Eric Rowland, Apr 29 2004
EXTENSIONS
More terms from Felix Fröhlich, Apr 24 2014
STATUS
approved