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 A048593 Converse numbers: composite Fibonacci numbers Fib(n) that are congruent to Legendre symbol (n/5) mod n. 0
 4181, 75025, 1346269, 165580141, 956722026041, 1548008755920, 2504730781961, 308061521170129, 14472334024676221, 1779979416004714189, 573147844013817084101, 26925748508234281076009 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 REFERENCES Lure of the Integers, Joe Roberts, "Integer 4181". (There is a misprint in the definition.) LINKS EXAMPLE 4181 is the 19th Fibonacci number, it is composite and it is congruent to (19/5) mod 19. MAPLE with(combinat):with(numtheory): n := 1:while n<200 do n := n+1: if fibonacci(n) mod n = L(n, 5) then if not isprime(fibonacci(n)) then print(fibonacci(n)):fi:fi:od: CROSSREFS Cf. A000045. Sequence in context: A238082 A072322 A045728 * A050937 A135953 A290846 Adjacent sequences:  A048590 A048591 A048592 * A048594 A048595 A048596 KEYWORD nonn AUTHOR STATUS approved

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Last modified May 7 12:26 EDT 2021. Contains 343650 sequences. (Running on oeis4.)