login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
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

Table of n, a(n) for n=1..12.

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

Jud McCranie

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

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